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Mark Wilson
 
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Default Grounding Rod Info

I recently had an electrician verify that I need a new grounding rod but
before he does the work I wanted to get clear regarding the manner in which
telephone, cable, roof mounted TV antenna, and water pipes should be
grounded to the main service ground.

The rod will be planted a few feet from the house just opposite the inside
service panel. Must the TV Antenna ground go all the way to the top of the
rod or is it okay to split-bolt to the grounding wire at or just below
ground level?

The main water pipe enters the house about 25 yards away from the grounding
rod. Is it acceptable to ground the cold water pipe to the service ground
from inside the house? In this case I would split-bolt to the service
ground wire just before it goes through the basement wall.

My house is cabled for cable TV (although I don't currently subscribe).
Where is the best (practical) place to ground the TV Cable? Split-Bolt
again to service wire as it leaves basement?

Finally, what about Telephone system ground? Split-bolt as it leaves
basement? Is this something the phone company must do (for demarcation
reasons) and if so, are they gonna charge me for it?

Yes, the electrician answered these questions for me already, but my
newsgroup search shows that answers vary and that sometimes the "pros" don't
always do things 100% right, so that's why I've come back here to trusty old
alt.home.repair.

Thanks for your thoughts.



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Don Phillipson
 
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"Mark Wilson" wrote in message
...
I recently had an electrician verify that I need a new grounding rod but
before he does the work I wanted to get clear regarding the manner in

which
telephone, cable, roof mounted TV antenna, and water pipes should be
grounded to the main service ground.

The rod will be planted a few feet from the house just opposite the inside
service panel. Must the TV Antenna ground go all the way to the top of

the
rod or is it okay to split-bolt to the grounding wire at or just below
ground level?


Your safest guide is the local municipal
licensing office which authorizes (and
perhaps inspects) new electric installations.

--
Don Phillipson
Carlsbad Springs (Ottawa, Canada)
dphillipson[at]trytel.com


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w_tom
 
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Thomas D. Horne has accurately summarized important points
as required by code. However effective earthing exceeds
code. Every incoming utility must make a less than 10 foot
connection where they all meet at your new central earth
ground rod. That includes connections from cable ground
block, from TV antenna and satellite dish wires before
entering building, and ground wire from telco supplied surge
protector in NID premise interface box. All earthing wires
must also be direct (not via other wires, no sharp bends, no
splices), and independent (not bundled with other non
grounding wires and separate from all other earthing wires
until they all meet at central earth ground). An old
expression that says a better ground is not neat. No clean
sharp bends. If an angled wire to earth ground is shorter,
then angle the wire rather than make it look clean, sharp, and
neat.

TV antenna is suppose to be earthed at shortest point. If
TV antenna is earthed by a separate ground rod, then a buried
solid copper wire (as sized according to code) must
interconnect that separate rod with the main central earth
ground rod.

If soil is non-conductive, than additional rods should be
attached to that central earth ground rod. Central earth
ground must be the best earthing point in the facility.
Poorly conductive soil includes sand, loom, gravel, or soils
bleached of ionic materials.

Some examples of how the earthing system should be
reinstalled-
http://www.cinergy.com/surge/ttip08.htm
http://www.psihq.com/iread/strpgrnd.htm
http://www.xantrex.com/support/docserve.asp?id=337

Of course, the grounding system must comply with what Thomas
D. Horne has posted since we earth for multiple reasons - one
is demanded by cited code.

Water pipe is safety grounded - not necessarily earth
grounded. Connection from water pipe must be to breaker box
safety ground bar because that ground wire is to remove
dangerous currents from the water pipe - a human safety
function.

Mark Wilson wrote:
I recently had an electrician verify that I need a new grounding rod but
before he does the work I wanted to get clear regarding the manner in
which telephone, cable, roof mounted TV antenna, and water pipes
should be grounded to the main service ground.

The rod will be planted a few feet from the house just opposite the
inside service panel. Must the TV Antenna ground go all the way to
the top of the rod or is it okay to split-bolt to the grounding wire
at or just below ground level?

The main water pipe enters the house about 25 yards away from the
grounding rod. Is it acceptable to ground the cold water pipe to
the service ground from inside the house? In this case I would
split-bolt to the service ground wire just before it goes through
the basement wall.

My house is cabled for cable TV (although I don't currently subscribe).
Where is the best (practical) place to ground the TV Cable? Split-Bolt
again to service wire as it leaves basement?

Finally, what about Telephone system ground? Split-bolt as it leaves
basement? Is this something the phone company must do (for demarcation
reasons) and if so, are they gonna charge me for it?

Yes, the electrician answered these questions for me already, but my
newsgroup search shows that answers vary and that sometimes the "pros"
don't always do things 100% right, so that's why I've come back here
to trusty old alt.home.repair.

Thanks for your thoughts.

  #4   Report Post  
volts500
 
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"Thomas D. Horne" wrote in message
...

Finally, what about Telephone system ground? Split-bolt as it leaves
basement? Is this something the phone company must do (for demarcation
reasons) and if so, are they gonna charge me for it?

The telephone system ground is attached using a saddle clamp and in most
areas that work is done by the telco staff at no cost to you. The rules
governing communications grounding in the US NEC require that the
conductor used to ground the communications wiring be kept to six feet
or less in length. If six feet will not get to the Service's accessible
grounding means then install a separate ground rod and bond it to the
service grounding electrode with a #6 AWG bonding conductor.



Didn't you mean to say 6 meters (20 ft.) instead of 6 feet Tom?


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Thomas D. Horne
 
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volts500 wrote:
"Thomas D. Horne" wrote in message
...

Finally, what about Telephone system ground? Split-bolt as it leaves
basement? Is this something the phone company must do (for demarcation
reasons) and if so, are they gonna charge me for it?


The telephone system ground is attached using a saddle clamp and in most
areas that work is done by the telco staff at no cost to you. The rules
governing communications grounding in the US NEC require that the
conductor used to ground the communications wiring be kept to six feet
or less in length. If six feet will not get to the Service's accessible
grounding means then install a separate ground rod and bond it to the
service grounding electrode with a #6 AWG bonding conductor.




Didn't you mean to say 6 meters (20 ft.) instead of 6 feet Tom?



Yes and thank you for catching that. I included the code reference
which correctly shows six meters. I guess I just shouldn't type so fast.
--
Tom



  #6   Report Post  
Mark Wilson
 
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Thanks for the help Thomas D. Horne and everyone else. Sorry about the
cut&paste manner in which I'm responding. I'm having newsgroup trouble.
The guy helping me is a retired electrician. We're waiting on the gas
company to label the gas lines before pounding the rod in the ground. Given
your answers I can see you're being more techincal and accurate than he was,
which is good! It's my job to go pick up the parts we'll need to do the
job.

Replies are in line.
Mark Wilson wrote:
I recently had an electrician verify that I need a new grounding rod but
before he does the work I wanted to get clear regarding the manner in

which
telephone, cable, roof mounted TV antenna, and water pipes should be
grounded to the main service ground.

The rod will be planted a few feet from the house just opposite the

inside
service panel. Must the TV Antenna ground go all the way to the top of

the
rod or is it okay to split-bolt to the grounding wire at or just below
.ground level?


You can attach the grounding conductors of other services to the
Electrical Service's Equipment's Grounding Electrode Conductor (EGC) at
any convenient point along it's exposed length.


Thanks I understand, (assuming the EGC is just a fancy way of saying
main-ground-wire-coming-from-the-service-panel-and-heading-toward-the-ground
ing-rod.) I'll use a split bolt to ground the outside TV antenna ground
conductor to the EGC after the EGC leaves the basement but before it reaches
the ground rod.


The main water pipe enters the house about 25 yards away from the

grounding
rod. Is it acceptable to ground the cold water pipe to the service

ground
from inside the house? In this case I would split-bolt to the service
ground wire just before it goes through the basement wall.


You may not make any connection of the EGC using a split bolt connector
or any other reversible splice. You can run the EGC from the bonded
buss bar of the service equipment to the pipe and a separate EGC from
the same buss bar to the driven rod. Alternatively you can run the EGC
to either the rod or the piping and from that electrode to the other
electrode.


Thanks for clearing that up. I'll bond the water pipe to the bus bar in the
service panel, and then run the main ground EGC from that same bus bar to
the ground rod. (Techincally, for the main EGC, I'll use the bolt-like
attachement provided at the bottom of said bus bar) Because I'll be
replacing the main EGC with fresh 4 gauge conductor, I'll probably just use
some extra 4 gauge for the pipe to bus conductor as well.


My house is cabled for cable TV (although I don't currently subscribe).
Where is the best (practical) place to ground the TV Cable? Split-Bolt
again to service wire as it leaves basement?

Yes you can use a split bolt connector to attach the grounding conductor
of other services to the EGC.


Thanks to you and "w_tom", I see I may be referring to something different
when I say TV cable ground. After the cable enters the house, it goes to a
standard RCA splitter and it's from there that there is some kind of bleed
off ground wire. It was this ground wire that I was referring to rather
than something coming off a block outside the house. Right now the plan is
to just split bolt the cable ground wire to the EGC just before it heads
outside through the basement wall. I'll will have a look at the outside
block for the TV Cable.


Finally, what about Telephone system ground? Split-bolt as it leaves
basement? Is this something the phone company must do (for demarcation
reasons) and if so, are they gonna charge me for it?

The telephone system ground is attached using a saddle clamp and in most
areas that work is done by the telco staff at no cost to you. The rules
governing communications grounding in the US NEC require that the
conductor used to ground the communications wiring be kept to six feet
or less in length. If six feet will not get to the Service's accessible
grounding means then install a separate ground rod and bond it to the
service grounding electrode with a #6 AWG bonding conductor.

(assuming six feet means six meters as was corrected earlier)

The six meters is no problem as the telephone line enters the house right
next to the service panel. However, I'm a little confused by what is meant
by "Service's accessible grounding means". "Accessible" being the key
word, I'm assuming you mean that Telco will ground to the EGC after exists
the service panel, but before it heads outside through the basement wall.


IV. Grounding Methods
800.40 Cable and Primary Protector Grounding.
The metallic member(s) of the cable sheath, where required to be
grounded by 800.33, and primary protectors shall be grounded as
specified in 800.40(A) through (D).
(A) Grounding Conductor.
(1) Insulation. The grounding conductor shall be insulated and shall be
listed as suitable for the purpose.


Hmm. Assuming this section "IV" is referring to the EGC, are you saying that
the main ground conductor must be insulated? And by insulated does that
mean plastic wire covering? I thought I'd be safe with a bare solid copper
4 gauge wire? I must be reading this wrong...

(2) Material. The grounding conductor shall be copper or other
corrosion-resistant conductive material, stranded or solid.
(3) Size. The grounding conductor shall not be smaller than 14 AWG.


Again, although this specifies 14 as the smallest, even 10 or 8 seems too
small. Maybe this part of the code is not referring to the main EGC?

It's very kind of you to take the time to respond, Mr. Horne. If you'll
indulge me in a little further clarification, I'd appreciate it all the
more, but I'm already plenty grateful at this point.

Thanks again.


  #7   Report Post  
w_tom
 
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Ground block is really nothing more than a connector that
attached to CATV cable and that permits a 10 AWG ground wire
to be connected. It is even sold in Home Depot with other
CATV cable accessories. Best to put grounding block on cable
outside building and as close to new ground rod as is
possible. Make distance from CATV to ground rod shorter with
minimal bends, etc. Yes that grounded RCA splitter
accomplishes same for human safety and NEC reqirements. But
transistor safety wants that connection to earth ground to be
closer to central earth ground. Also an outside ground block
to ground rod connection makes it easier to keep that ground
wire separate from other non-grounded wires.

Telco provides a "Service's accessible grounding means" in a
box called NID. Their 10 AWG earth ground wire connects their
NID box mounted outside (so that it is accessible) to that
earth ground rod. Some installers want to make that 10 AWG
wire look neat. They will even 'split bolt' attach it to the
breaker box ground wire. However better trained installers
will run their ground wire directly to the top of that ground
rod - as should be the CATV wire ground. All grounds should
run indepenently until they all meet at central earth ground.
This last requirement is not required in code but creates a
more robust and effective earth ground.

As a reminder to others, smart move to have all utilities
located before pounding down the rod.

Mark Wilson wrote:
Thanks to you and "w_tom", I see I may be referring to something different
when I say TV cable ground. After the cable enters the house, it goes to a
standard RCA splitter and it's from there that there is some kind of bleed
off ground wire. It was this ground wire that I was referring to rather
than something coming off a block outside the house. Right now the plan is
to just split bolt the cable ground wire to the EGC just before it heads
outside through the basement wall. I'll will have a look at the outside
block for the TV Cable.
...
The six meters is no problem as the telephone line enters the house right
next to the service panel. However, I'm a little confused by what is meant
by "Service's accessible grounding means". "Accessible" being the key
word, I'm assuming you mean that Telco will ground to the EGC after exists
the service panel, but before it heads outside through the basement wall.

  #8   Report Post  
Mark Wilson
 
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Thanks for your help Tom. I also explored the links you provided and found
them helpful. In fact, part of the reason I started looking into this is
because I have lost a modem. Although I have no reason to believe there
have been multiple grounds in the past, I'll be sure everything goes to the
same place before I'm done.

Ground block is really nothing more than a connector that
attached to CATV cable and that permits a 10 AWG ground wire
to be connected. It is even sold in Home Depot with other
CATV cable accessories. Best to put grounding block on cable
outside building and as close to new ground rod as is
possible. Make distance from CATV to ground rod shorter with
minimal bends, etc. Yes that grounded RCA splitter
accomplishes same for human safety and NEC reqirements. But
transistor safety wants that connection to earth ground to be
closer to central earth ground. Also an outside ground block
to ground rod connection makes it easier to keep that ground
wire separate from other non-grounded wires.


Hmm. Well, I checked and there's no ground whatsoever coming off the CATV
line at the point it enters the house. I'd have to install a new one
outside in order to run a ground line from the entrance point, and that side
of the house is the exact opposite of where I plan to put the ground rod.
The CATV comes from the street to the top of my house and then runs down
before meeting a splitter and entering the house. Becuase I don't currently
subscribe to Cable (and don't plan to), I think I'll just disconnect the
cable so that it never even enters the house and then I'll just forget about
grounding it. Is there any reason why this would be unsafe or cause
electrical trouble?


Telco provides a "Service's accessible grounding means" in a
box called NID. Their 10 AWG earth ground wire connects their
NID box mounted outside (so that it is accessible) to that
earth ground rod. Some installers want to make that 10 AWG
wire look neat. They will even 'split bolt' attach it to the
breaker box ground wire. However better trained installers
will run their ground wire directly to the top of that ground
rod - as should be the CATV wire ground. All grounds should
run indepenently until they all meet at central earth ground.
This last requirement is not required in code but creates a
more robust and effective earth ground.


Well, the Network Interface Box I have now is really old and in bad shape.
There's no NID or block or anything outside of house. The line comes
straight in. (I'll spare you the details, but let me just say that I'll be
calling Telco as soon as I get my electrical troubles in order.) Even so,
I'm glad you mentioned it. I can leave the top of the ground rod exposed
and that way Telco can have the option to run a conductor straight to it,
rather than using the split-bolt method. At this point I have no idea what
they will do or if they will even install an outside NID. One way or the
other, the current telephone junction box needs replacing.

If I'm following your line of thinking, then wouldn't it be slightly better
to run the TV Antenna ground straight to the grounding rod tip as opposed to
split-bolting it to the main ground (coming from the service panel and
heading towards the rod)?

Oh, an in case I don't hear from Thomas Horne, is bare 4 gauge copper
conductor appropriate for grounding the service panel to the grounding rod,
or must it be insulated with plastic? (I was just at Lowes and the
"x-electrician" there says I only need the bare wire)

Thanks. Sorry for being so caught up in the details. I really want to do
this right and do it safe, and I'm not getting the same answers from the
local "Pros".

As a reminder to others, smart move to have all utilities
located before pounding down the rod.



  #9   Report Post  
Thomas D. Horne
 
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Replies are in line.

Mark Wilson wrote:
Thanks for the help Thomas D. Horne and everyone else. Sorry about the
cut&paste manner in which I'm responding. I'm having newsgroup trouble.
The guy helping me is a retired electrician. We're waiting on the gas
company to label the gas lines before pounding the rod in the ground. Given
your answers I can see you're being more techincal and accurate than he was,
which is good! It's my job to go pick up the parts we'll need to do the
job.


Replies are in line.
Mark Wilson wrote:

I recently had an electrician verify that I need a new grounding rod but
before he does the work I wanted to get clear regarding the manner in


which

telephone, cable, roof mounted TV antenna, and water pipes should be
grounded to the main service ground.

The rod will be planted a few feet from the house just opposite the


inside

service panel. Must the TV Antenna ground go all the way to the top of


the

rod or is it okay to split-bolt to the grounding wire at or just below
.ground level?


You can attach the grounding conductors of other services to the
Electrical Service's Equipment's Grounding Electrode Conductor (EGC) at
any convenient point along it's exposed length.



Thanks I understand, (assuming the EGC is just a fancy way of saying
main-ground-wire-coming-from-the-service-panel-and-heading-toward-the-ground
ing-rod.) I'll use a split bolt to ground the outside TV antenna ground
conductor to the EGC after the EGC leaves the basement but before it reaches
the ground rod.


Once again I have typed too fast. The abbreviation I meant to use is GEC.


The main water pipe enters the house about 25 yards away from the
grounding rod. Is it acceptable to ground the cold water pipe to the

service ground
from inside the house? In this case I would split-bolt to the service
ground wire just before it goes through the basement wall.


You may not make any connection of the EGC using a split bolt connector
or any other reversible splice. You can run the EGC from the bonded
buss bar of the service equipment to the pipe and a separate EGC from
the same buss bar to the driven rod. Alternatively you can run the EGC
to either the rod or the piping and from that electrode to the other
electrode.



Thanks for clearing that up. I'll bond the water pipe to the bus bar in the
service panel, and then run the main ground EGC from that same bus bar to
the ground rod. (Techincally, for the main EGC, I'll use the bolt-like
attachement provided at the bottom of said bus bar) Because I'll be
replacing the main EGC with fresh 4 gauge conductor, I'll probably just use
some extra 4 gauge for the pipe to bus conductor as well.


My house is cabled for cable TV (although I don't currently subscribe).
Where is the best (practical) place to ground the TV Cable? Split-Bolt
again to service wire as it leaves basement?


Yes you can use a split bolt connector to attach the grounding conductor
of other services to the EGC.



Thanks to you and "w_tom", I see I may be referring to something different
when I say TV cable ground. After the cable enters the house, it goes to a
standard RCA splitter and it's from there that there is some kind of bleed
off ground wire. It was this ground wire that I was referring to rather
than something coming off a block outside the house. Right now the plan is
to just split bolt the cable ground wire to the EGC just before it heads
outside through the basement wall. I'll will have a look at the outside
block for the TV Cable.


Finally, what about Telephone system ground? Split-bolt as it leaves
basement? Is this something the phone company must do (for demarcation
reasons) and if so, are they gonna charge me for it?


The telephone system ground is attached using a saddle clamp and in most
areas that work is done by the telco staff at no cost to you. The rules
governing communications grounding in the US NEC require that the
conductor used to ground the communications wiring be kept to six feet
or less in length. If six feet will not get to the Service's accessible
grounding means then install a separate ground rod and bond it to the
service grounding electrode with a #6 AWG bonding conductor.


(assuming six feet means six meters as was corrected earlier)

The six meters is no problem as the telephone line enters the house right
next to the service panel. However, I'm a little confused by what is meant
by "Service's accessible grounding means". "Accessible" being the key
word, I'm assuming you mean that Telco will ground to the EGC after exists
the service panel, but before it heads outside through the basement wall.


That primary telephone protector should be located outside the home.
That will keep much of the surge and spike energy outside of your home.

IV. Grounding Methods
800.40 Cable and Primary Protector Grounding.
The metallic member(s) of the cable sheath, where required to be
grounded by 800.33, and primary protectors shall be grounded as
specified in 800.40(A) through (D).
(A) Grounding Conductor.
(1) Insulation. The grounding conductor shall be insulated and shall be
listed as suitable for the purpose.



Hmm. Assuming this section "IV" is referring to the EGC, are you saying that
the main ground conductor must be insulated? And by insulated does that
mean plastic wire covering? I thought I'd be safe with a bare solid copper
4 gauge wire? I must be reading this wrong...


(2) Material. The grounding conductor shall be copper or other
corrosion-resistant conductive material, stranded or solid.
(3) Size. The grounding conductor shall not be smaller than 14 AWG.



Again, although this specifies 14 as the smallest, even 10 or 8 seems too
small. Maybe this part of the code is not referring to the main EGC?

It's very kind of you to take the time to respond, Mr. Horne. If you'll
indulge me in a little further clarification, I'd appreciate it all the
more, but I'm already plenty grateful at this point.

Thanks again.


That part of the code CEOs not refer to the Electrical Service GEC but
rather to the Communications Grounding Conductor. This conductor bonds
the communications protector to the GEC or the other accessible
grounding means. W_Tom's suggestion to run the communications grounding
conductor to the Ground rod itself will cause a few challenges. One is
that conductors smaller than #6 must have protection from physical
damage. Lawn mowers, edge trimmers, & weed eaters expose GECs to severe
physical damage so any conductor that is run within reach of such
equipment must be number four or be run in protective raceway. If the
conductors would run adjacent to each other anyway than a split bolt or
saddle clamp would be just as effective.
--
Tom

  #10   Report Post  
MargieKay
 
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"Mark Wilson" wrote in message
...
I recently had an electrician verify that I need a new grounding rod

but
before he does the work I wanted to get clear regarding the manner in

which
telephone, cable, roof mounted TV antenna, and water pipes should be
grounded to the main service ground.

The rod will be planted a few feet from the house just opposite the

inside
service panel.


Did the electrician say you need a NEW grounding rod or a SECOND grounding
rod? The reason that I am asking is that a local electrical inspector just
told me that the "new electrical code" now calls for TWO grounding rods to
be installed 6 feet apart -- instead of just one grounding rod. He said one
continuous #6 grounding wire would go from one rod to the next rod 6 feet
away (and looped around it) and then to the neutral block on the electric
panel box.

I know nothing about how all of this works and will probably just have an
electrician do it. But, when I saw your subject line, I figured I'd pass on
what I was just told in case it helps.




  #11   Report Post  
Mark Wilson
 
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Thanks to both Toms (and everyone else) for all the clarifications. Words
are cheap, but I really do appreciate the help. I'm ready to let the
Electrician lead the way, but now I can make sure all is on the up and up.

Of course, knowing me, there's one last detail. Power comes into my house
to a main breaker box, then goes out to a separate modern service panel.
The main breaker box is nothing more than a 100 amp breaker with no bus bars
or anything like that. (Sorry if that was obvious). Power goes through
this main breaker and over to a separate modern service panel. Likewise, a
4 gague copper ground conductor leaves this main breaker box and goes out to
the modern service panel.

Currently, the GEC leaves from the main breaker box and goes out through the
basement wall to earth ground.

If I understand correctly, from what I've learned here, the new setup should
have the GEC going from the ground bar of the modern service panel out
through the wall to the grounding rod, instead of the GEC coming from the
initial main breaker box. Is that correct?


(If the correct method is to run the GEC from the initial breaker box, then
does that mean the water pipe ground conductor should also be grounded to
this same box as opposed to using the modern service panel's ground bus
bar?)

And with that, I'll let this long thread putter out. Thanks for sticking
with me and my poor newserver access. lol.



  #12   Report Post  
Mark Wilson
 
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The main breaker box is nothing more than a 100 amp breaker with no bus

bars
or anything like that.


Just to be clear, there is a small 4 inch bar that accepts the incoming
ground and allows for the copper conductor to leave the box to go to the
earth ground and another to go to the modern service panel. I just meant
there's no modern style bus bar and no room for additional circuits or
anything like that.


  #13   Report Post  
volts500
 
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"w_tom" wrote in message
...

Telco provides a "Service's accessible grounding means" in a
box called NID. Their 10 AWG earth ground wire connects their
NID box mounted outside (so that it is accessible) to that
earth ground rod. Some installers want to make that 10 AWG
wire look neat. They will even 'split bolt' attach it to the
breaker box ground wire. However better trained installers
will run their ground wire directly to the top of that ground
rod - as should be the CATV wire ground. All grounds should
run indepenently until they all meet at central earth ground.
This last requirement is not required in code but creates a
more robust and effective earth ground.

As a reminder to others, smart move to have all utilities
located before pounding down the rod.



There is no such thing as a "central earth ground" unless only _one_
grounding electrode is used.....a very poor practice in itself (with the
possible exception of a metal well casing)....much better to have _multiple_
grounding electrodes bonded together. All grounding electrodes are bonded
together to form a _single_ grounding electode _system_. The ground rod
that is being installed is merely a _supplement_ to the main grounding
electrode.......in this case the metal water pipe. Not a good idea to try
to dump all that on a single ground rod.......a single ground rod will in
fact become a choke to lightning trying to get into the ground. That single
ground rod should be supplemented by at least another ground rod 6 feet away
(or use a delta ground), or a ground ring can be installed with a minimum
#2.....and catch the cable TV while you are at it.

The basic idea is too run an unbroken GEC from the main panel to the
underground water pipe (min. #4) and suppliment that with a ground rod (or
two). Then bond all systems together. The idea is that when all the
systems are bonded together, ALL will come up to the same voltage (can be ma
ny thousands of volts), thus _not_ allowing a destructive current flow in
equipment served from different systems....like a modem. Don't forget to
jumper around the water meter and bond the hot water.

Bottom line, electric system grounding is a very misunderstood subject and
needs to be done by people who know and care about how to install it.

You still have your inside metal gas line to deal with.......you should call
your gas co. to see if they allow an (inside) connection to the electric
grounding system as required by NEC.

I hope that after going through all that trouble that you are also going to
install a lightning arrestor at the electric meter or service panel. Then
use a decent point of use surge protector for the computer that has
provision for power _and_ phone....cable too if you ever use a cable modem.

Also, since you said that you have a subpanel in another thread, you should
check to see that the subpanel is fed from the main panel with a _4_ wire
feeder (2 hots, neutral, equipment ground).


  #14   Report Post  
Mark Wilson
 
Posts: n/a
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Volts500,

There is no such thing as a "central earth ground" unless only _one_
grounding electrode is used.....a very poor practice in itself (with the
possible exception of a metal well casing)....much better to have

_multiple_
grounding electrodes bonded together. All grounding electrodes are bonded
together to form a _single_ grounding electode _system_. The ground rod
that is being installed is merely a _supplement_ to the main grounding
electrode.......in this case the metal water pipe. Not a good idea to try
to dump all that on a single ground rod.......a single ground rod will in
fact become a choke to lightning trying to get into the ground. That

single
ground rod should be supplemented by at least another ground rod 6 feet

away
(or use a delta ground), or a ground ring can be installed with a minimum
#2.....and catch the cable TV while you are at it.


I guess I could be convinced to install 2 rods. I'm doing the work to
install the first.


The basic idea is too run an unbroken GEC from the main panel to the
underground water pipe (min. #4) and suppliment that with a ground rod (or
two). Then bond all systems together.


If I plant the ground rods just outside the wall of my service panel, I'd
have to dig 20 yards over and eight feet down to bring the #4 to the water
pipe. If I run #4 from the ground bar to the water pipe from inside the
house and then do two ground rods, won't that be enough?

The idea is that when all the
systems are bonded together, ALL will come up to the same voltage (can be

ma
ny thousands of volts), thus _not_ allowing a destructive current flow in
equipment served from different systems....like a modem. Don't forget to
jumper around the water meter and bond the hot water.


If I bond the hot water pipe, I'm guessing I would do it the same way as the
cold (from the inside).

What do you mean by "jumping around" the water meter?

Bottom line, electric system grounding is a very misunderstood subject and
needs to be done by people who know and care about how to install it.


Don't get me wrong. I trust the advice here or I wouldn't be here. But
here's the bottom line for me. Whatever electrician the previous home owner
hired didn't do the job right, the electrician I hired to inspect the home
before I bought it didn't see the problems, and the electrician I'm
currently paying to fix things now is contradicting the advice I'm getting
here. I guess I could go to the yellow pages again, but at this point I if
I don't know what "right" is, I don't think I'll ever have peace of mind
over what work is finally done.

You still have your inside metal gas line to deal with.......you should

call
your gas co. to see if they allow an (inside) connection to the electric
grounding system as required by NEC.


I had the gas guy out ther other day. Although the pipes I see are metal,
he said the lines underground were plastic, but I'll make the call to make
sure.


I hope that after going through all that trouble that you are also going to
install a lightning arrestor at the electric meter or service panel.


I'll look into that, but it seems like overkill at this point.

Then
use a decent point of use surge protector for the computer that has
provision for power _and_ phone....cable too if you ever use a cable modem.


I have a $35 surge protector I use for electrical and telephone.


Also, since you said that you have a subpanel in another thread, you should
check to see that the subpanel is fed from the main panel with a _4_ wire
feeder (2 hots, neutral, equipment ground).


Power enters the house in the form of two hot conductors going to the single
100A breaker box
and then exit the box, going to the modern service panel. The neutral
conductor coming into the house
goes to a short metal "bar" which is bonded to the box itself, and then it
also leaves the box and goes
to the neutral bar of the modern service panel. From inside the 100A
breaker box, from that same short metal "bar" there are also two 4 gague
bare copper conductors that leave the box. Currenly, one leaves the box and
goes through the basement wall and out to earth ground. The other copper
conductor leaves the box and goes to the ground bus bar of the modern
service panel.

Thanks keeping me straight on the details.








  #15   Report Post  
Mark or Sue
 
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"Mark Wilson" wrote in message
...
Mark Wrote:
It is required to connect the GEC to the service equipment without any
splices between the service equipment and the electrode. Your service
equipment stops at the 100A disconnect. From that point on, neutral and
ground should always be kept separate and panels are no longer called
service rated panels.


Okay, so if I understand what you're saying, the 100A breaker box is what
the NEC would call my "service equipment" and therefore it is from this

box
that I should run the GEC.


Correct.


So hopefully your modern panel has the neutral bus
ISOLATED from the grounding bus and chassis. Hopefully, the #4 wire you
mentioned goes only to the grounding bus, which in turn must be bonded to
the chassis.


correctly described


Good! Someone knew what they were doing.


There is no problem sinking another ground rod at the modern
panel and connecting it to the grounding bus. This will just expand and
improve your grounding electrode system.


I'm not adding a second grounding rod. I'm just trying to replace my
current grounding rod and I intend to ground everything to that same

point.

But because this grounding bus is a
splice, the primary GEC can not be done this way -- but supplimental
bonding can.


I'm confused as to why I can't just run the GEC from the 100A breaker box
because to my understanding it would then NOT be a splice. Is it because

at
this point the ground and neutral are the same and have not yet separated?


Sorry, I wasn't clear when I said "panel". You must connect the mandatory
GEC at the 100A small disconnect box (or other connected service equipment).
You may NOT run the mandatory GEC from your modern panel, because it is not
part of your service equipment. It sounds like you want to ground from the
proper place, which is at the service equipment, which is where neutral and
ground are the same wire or bus.

In your other post, you mentioned a water pipe ground. We just went through
this in "Ground Rod Questions - summary". To summarize, if you have a metal
water pipe that is in contact with the earth for 10 feet or more, you MUST
use it as your primary grounding electrode. You must connect to it within 5'
from where the water pipe enters the house. This wire must be unspliced from
the water pipe to the service equipment neutral lug or wire. If you have a
water pipe ground, in most cases you must install a second electrode which
is usually a single rod. You shouldn't need two rods, but if you replace
your water pipe with plastic, then you do need two. Putting two in now
prepares you for the future and improves your grounding electrode system.
Additional rods must be at least 6' from any other rods in the same
grounding system. Alternatively, if you switch to plastic water service,
leave the old pipe buried in the ground and use that as your second
electrode (if you can get an unspliced wire to it).

Jumping around the meter means clamping a #4 wire between the input and
output sides of the meter. You can't be sure if a meter is conductive, so
you must put a jumper around it. This only applies if the meter at your
house between the buried water pipe and your inside pipes. My water meter is
at the street, and you don't jumper those.

--
Mark
Kent, WA





  #16   Report Post  
w_tom
 
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Attitude of code is that water pipe is not sufficient as the
primary or reliable earth ground connection. A separate
ground rod (or something equivalent) is required even if water
pipe earthing is available. Other incoming utilities will use
that ground rod as central earth ground; not water pipe.
Connection to water pipe is supplemental earthing to new
installations. Connection to one or multiple earth ground rod
(or whatever else you use for the earthing system), all at
same point, becomes single point earth ground. Everything
earths to multiple ground rods at same point. Even the
television aerial should make some connection to that single
point earth ground before entering a building even though the
aerial itself has a direct connection to a separate ground rod
- to fully optimize earthing for surge protection. These
exceed code requirements to make a superior protection
'system'.

That connection to water pipe is primarily to remove
currents from pipes - for human safety. Same safety reason is
why hot water pipes would also be grounded to panel ground.
If water pipe is also being used

Code requires a second ground rod if the first does not
measure less than 25 ohms. If second rod does not make less
than 25 ohms, then a third rod is not required - by code.
Code is not optimized for effective surge protection. If
earth is so non-conductive as to not supply less than 25 ohms,
then a more serious earthing system should be installed such
as halo ground, plate electrodes, or Ufer grounding. One rod
will make a minimally sufficient earthing connection in most
cases. Two rods will make every 'whole house' protector more
effective. The most important component in a surge
protection 'system' is its earth ground. Earthing and
distance of wire to that central earth ground will often be
the 'choke point' for system effectiveness. Additional money
spent on surge protection often is best spent on enhancing the
single point earth ground.

Code does not define how that earth resistance is to be
measured. Most locations will get less than 25 ohms with only
one ground rod. However, considering how important that
earthing system is also for transistor safety, then a second
rod is cheap insurance. Utility will install massive
grounding networks underneath a substation and still obtain
resistance on the order of 2 ohms. The first rod will lower
resistance. Every additional rod will provide less
improvement.


'nuther Bob wrote:
On Sat, 12 Jul 2003 03:22:50 GMT, "Mark or Sue"
wrote:
To summarize, if you have a metal water pipe that is in contact
with the earth for 10 feet or more, you MUST use it as your
primary grounding electrode.


WOuld "MUST" still apply if the proper attachment location to the
water pipe is 35 feet from the panel ? Or would the code then
prefer two grounding rods ?

  #17   Report Post  
volts500
 
Posts: n/a
Default Grounding Rod Info


"w_tom" wrote in message
...

Attitude of code is that water pipe is not sufficient as the
primary or reliable earth ground connection.


That's just not true, Tom. An underground metal water pipe is indeed a very
good grounding electrode. Why then does NEC (2002)Section 250.30(4)
_specifically_ require that an underground water pipe (and/or structural
steel) be used as the primary grounding electrode? Why then does the NEC
allow _made_ grounding electrodes (ground rods,etc) ONLY when a water ground
or structural steel is not available?

A separate
ground rod (or something equivalent) is required even if water
pipe earthing is available.



The ONLY reason that a ground rod is required by NEC to _supplement_ a water
ground is because of the distinct possibility that the metal water pipe may
be replaced by the water co.......leaving the system with no ground at all.
While a single ground rod is not the best ground, it's _certainly_ better
than none at all.


Other incoming utilities will use
that ground rod as central earth ground; not water pipe.



Again, just not true. The other utilities will grab on to any ground that
they can find. The NEC indeed requires that the electric service have
provision for same......even if it's just a bare #6 hanging out of the
bottom of the electric panel. There is not such thing as "central earth
ground" as you describe it.......and is in fact ludicrous to think that a
single ground rod is the "central earth ground." A single ground rod is
about the worst possible grounding electrode permitted by NEC.......it just
can't dissipate near as many electrons in a given time time as compared to a
water ground, ufer, structural steel, or a ground ring. In fact, it if you
try to dump all that on a single ground rod it will become a choke. That's
why, when installing a single ground rod (only) as a supplement to a better
ground, such as a water ground, that the wire to the an _individual_ ground
rod, REGARDLESS of the size of service only needs to be a #6 wire (per
NEC)........the ground rod just won't dissipate any more electrons than the
#6 can handle.


Connection to water pipe is supplemental earthing to new
installations.


No, it is _not_. It is the _primary_ grounding electrode, if available.
Problem is, these days plastic pipe is used. Any interior metal water
piping is connected to the neutral busbar to clear ground-faults should they
become energized.

Connection to one or multiple earth ground rod
(or whatever else you use for the earthing system), all at
same point, becomes single point earth ground.


No, connection (bonding) of multiple grounding electrodes forms a _single_
grounding electrode _system_. If you want to call something "a central
earth ground" the service entrance neutral busbar would be a more accurate
description. Even microwave towers have at least 100 or more Cad Welds
bonding every possible piece of metal and ground together. Where is the
"central earth ground" on that? There is _no_ single grounding point. If
you're referring to a single grounding connection point on a micowave tower
before all cables enter the building, then the corresponding single
grounding connection point on a house is basically the service equipment
neutral busbar. And if you want to start rambling about differential and
common mode surges......then you should at least recognize that, indeed, the
service entrance neutral busbar is _where_ the neutral and the equipment
grounding conductors are bonded together.......and _think_ about _that_
before you respond.


Everything
earths to multiple ground rods at same point.


Yeah, like the neutral busbar in the service equipment! It's not a radar
station, Tom.


Even the
television aerial should make some connection to that single
point earth ground before entering a building even though the
aerial itself has a direct connection to a separate ground rod
- to fully optimize earthing for surge protection. These
exceed code requirements to make a superior protection
'system'.

That connection to water pipe is primarily to remove
currents from pipes - for human safety.



No, the primary purpose of a metal underground water pipe is to ground the
electric system.


Same safety reason is
why hot water pipes would also be grounded to panel ground.
If water pipe is also being used

Code requires a second ground rod if the first does not
measure less than 25 ohms. If second rod does not make less
than 25 ohms, then a third rod is not required - by code.
Code is not optimized for effective surge protection.



THAT, I will concur. With more and more plastic being used these days, it's
very difficult to obtain a decent electric system ground. It would not be
much of a hardship on electrical contractors for the NEC to require a Ufer
(concrete-encased) grounding system......they just need to be there before
the concrete gets poured. Make it a requirement to get the OK to pour, just
like bug spray is required in most areas.


If
earth is so non-conductive as to not supply less than 25 ohms,
then a more serious earthing system should be installed such
as halo ground, plate electrodes, or Ufer grounding. One rod
will make a minimally sufficient earthing connection in most
cases. Two rods will make every 'whole house' protector more
effective. The most important component in a surge
protection 'system' is its earth ground.



Totally agree.


Earthing and
distance of wire to that central earth ground will often be
the 'choke point' for system effectiveness. Additional money
spent on surge protection often is best spent on enhancing the
single point earth ground.

Code does not define how that earth resistance is to be
measured. Most locations will get less than 25 ohms with only
one ground rod. However, considering how important that
earthing system is also for transistor safety, then a second
rod is cheap insurance. Utility will install massive
grounding networks underneath a substation and still obtain
resistance on the order of 2 ohms. The first rod will lower
resistance. Every additional rod will provide less
improvement.


'nuther Bob wrote:
On Sat, 12 Jul 2003 03:22:50 GMT, "Mark or Sue"
wrote:
To summarize, if you have a metal water pipe that is in contact
with the earth for 10 feet or more, you MUST use it as your
primary grounding electrode.


WOuld "MUST" still apply if the proper attachment location to the
water pipe is 35 feet from the panel ? Or would the code then
prefer two grounding rods ?




  #18   Report Post  
Mark Wilson
 
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Volts500,

Wow, thanks for the generously long reply.

Another thing......it's _not_ a good idea to be working on the electric
grounding system while the system is energized......you can be electrocuted
if the right conditions prevail (such as a low ampere ground-fault that
hasn't been cleared). Best to do as much preparation as possible (like
drilling holes, running ground wire, driving ground rods, etc.), then shut
down the main disconnect before
removing the existing grounding system and fully install the new system
before re-energizing.......plus it can get hazardous when installing bare
conductors in energized panels.


Well, the truth is I didn't discover that I need a new grounding rod, I
discovered, upon tracing the GEC, that the conductor was severed due to
corrosion. Right now the only ground I have is #4 going from the ground bar
(in the modern service panel) to the cold water pipe inside the house. I'm
not doing anything without the electrician, and nothing without shutting
down the main disconnect first.

The first thing that I would do is determine that the TV antenna is as far
away as possible from any overhead electric lines and the electric service
drop. I would then drive an 8 or 10 foot ground rod directly under the
antenna mast
(assuming roof mount), at least 18" away from the house...enough to get
outside the roof drip line.


Then, that's what I'll do. (or hire someone to do)


I would then drive another 8' ground rod (again, outside the roof drip

line)
close to the electric service and at least 6' (or more) from the TV antenna
ground rod.

I would then run a #4 bare stranded copper wire from the neutral busbar in
the first (main) disconnect box to the ground rod installed close to the
electric service.


Right, understanding that a the point of the first main disconnect box the
"netural" busbar is the only busbar there is, and it is at this same bar
that the ground conductors originate as well.

Pull enough extra wire to get to the antenna ground rod
without splice, then slip an acorn grounding connector over the wire and
attach it to the first ground rod.......then use another acorn to attach

the
#4 to the antenna ground rod (leave enough room at the top of the ground

rod
for another acorn.


Usually once the all the connections are made to the ground rods they are
driven below ground. If you want the connections to be accessible, you can
cut an 8 or 10 inch long piece of 4 inch PVC (gray, sunlight resistant)
conduit and install it around the ground rod at finished grade level.
Exposed connections to ground rods are required to be protected or driven
below finished grade.

I would then attach an antenna discharge unit (on a non-metallic surface)

to
the side of the house about a foot or so above grade. After attaching a
ground clamp to the TV mast, I would run a #8 or #10 copper wire from the
mast ground clamp, through the lug on the antenna discharge unit, unbroken,
and on to the antenna ground rod, using another acorn. The antenna

lead-ins
are then attached to the antenna discharge unit and brought into the house.

OK, antenna is done. On to interior gas line. The NEC requires that an
_interior_ gas line be connected to the grounding electrode system. After
calling
the gas co. to be sure it's OK with _them_, one way to accomplish that goal
would be to be to install a ground clamp on the gas line closest to the

main
disconnect and run a #4 bare to the neutral busbar in the main disconnect.


Okay, I still need to make that call.

Ok, gas is done. On to the water ground. I don't know where your water
heater is located or if you have a water meter inside the house, but the
idea is the same as for the TV antenna run.......install a ground clamp on
the metal hot and cold water pipes near the water heater.....then install
ground clamps on both sides of the water meter. Then (if possible) run a

#4
bare from the neutral busbar in the main diconnect, UNBROKEN, through the
ground clamps on the water heater, through the ground clamps on the water
meter,


To restate, the water heater, incoming gas line, and incoming power line
(and the service panels) are all in one corner of the basement so those are
short and easy access. However, the water line actually enters the home
about 30 feet away, and there's one right angle turn to get there, although
I could probably make the bend much more gradual. Because the water meter
is located less than three feet from the point at which the the water pipe
enters the home, if I install ground clamps on both sides of the water
meter, I'm assuming I won't need to worry about another clamp "within 5
feet of where the water pipe enters the house". Knowing it's a 4 foot run
to the water heater and another 30 foot run to the water meter, do you still
recommend using an UNBROKEN wire?

leaving enough of a loop at the water meter so that it can be
replaced without disrupting the continuity ot the GEC,


"it" meaning the water meter.. in case it ever needs replacing.. got it.

and on to a point
within 5 feet of where the metal underground water pipe enters the house.
It doesn't have to be done exactly like that, but that's the way I would do
it, if possible. At the very least an unbroken #4 must be ran from the
neutral busbar to within 5 feet of where the water pipe enters the
house.......then jumper the water meter and hot water with short pieces if
you want.


Okay, this sounds like a good way to do it. Because using a conductor to
join the water pipe and the grounding rods OUTDOORS would be very difficult,
is grounding the water pipe from the inside (as you describe) really an
adequate substitute? Also, because the ground rods will be located at one
part of front yard while the water pipes enter the home about 20 yards away,
will this be a problem having "two separate ground" locations, so to speak?


The neutral and the equipment grounding conductors are bonded to each other
and the service equipment enclosure _at_ the main disconnect _only_. Your
description of the feeder from the main disconnect to the panelboard

sounded
kind of hokey.......the cable running to the panelboard should be 4 wire

(in
the _same_ cable or conduit) and the panelboard neutral busbar should be
isolated from ground (look to see if a green screw goes through the
panelboard neutral busbar and into the back of the panel, if so, remove it.
The green screw is called the "main bonding jumper," but it also can be a
wire or strap in-leu of the green screw.)


I'm just going to have to get some images up for you to see. I've tried to
find online diagrams or descriptions of how the panelboard should looked
properly wired, but I can't find any. Let me try one more time to describe
it. Incoming power to my house has three stranded conductors contained in
one cable. The two hot conductors are insulated and the third is bare
metal. These conductors are several times the size of a 4 gague wire,
including the bare one. Inside the main disconnect box, the two hot
conductors go to the solitary 100A Breaker. The bare metal conductor goes
to what I guess we have been calling the neutral "busbar". This little
busbar is grounded to the box itself, and from this busbar a relatively
smaller #4 wire originates and, acting as GEC, goes out to earth ground. A
second #4 wire also originates from this bus bar and goes out to the
grounding bus bar of the panelboard (which I have been calling the modern
service panel). Leaving from the main disconnect box is a cable exactly
like the one that comes into the main disconnect box. The two hots go to
the 100A breaker IN the panelbox. The neutral goes to neutral bus bar of
the panelboard. There is no green screw that I can see, but it seems clear
that a metal bar grounds one bus to the box itself.

Although the electrician already said it was okay, I'll have him look at it
again to be certain. I really am going to let him mess with it rather than
doing it myself.

OK, water ground done. On to cable TV. While you say that you won't be
using cable, now is the time to get a decent ground connection to
it.........if cable is installed later and not grounded properly, the TV,
VCR and/or cable modem, and possibly the computer will be subject to

damage.
From the outside cable TV ground block, an insulated #10 can be split
bolted to any of
the above mentioned ground wires.


I may not understand the term, but there really isn't any kind of cable
ground block outside the house. Cable runs down the house to a splitter,
then enters the house in two places. I guess I could install some kind of
"antenna discharge unit" and run a ground from there. But you're saying I
should run the #10 outside the house all the way to one of the grounding
rods? It's literally on the opposite side of the house from where the rods
will be. It would be a very long horizontal run at best IF I dug under my
sidewalk and/or porch. If I don't go under the concrete, then I'd have to
go along side the house and over the front door and past a few windows. My
wife would kill me. Would it be unsafe to run the #10 ground through the
INSIDE of the house? (That's the way it is now)

Now for the phone. The telephone primary protector should be installed
outside the house by the tele co. and attached to the bare #4 that's coming
outside to catch the ground rod......or to the ground rod......whatever
floats your boat. This connection is best made by the tele co. people
though, if/when they come out to get the demark box right.


Ok, will do.


The ground conductors connecting the phone and cable ground blocks to the
grounding electrode system are usually a insulated
wire from the ground block to where they are connected to the grounding
electrode system.

Like I said, that's how I would do it. Without seeing it, that's the best
I can do for you. Actual installation may differ somewhat, but that's the
general idea. One thing is for sure, as slow as I type, I could have done
had the job done for you in the same amount of time that it has took me to
type this post.


Tell me, what DO you get out of helping out guys like me? Is is just good
samaritanism? I'm always amazed at how generous some people are with their
knowledge and time. I really do appreciate it.


Please get it inspected by a _real_ electrical inspector.


I will Volts500. Thanks for your genuine concern.


If your neutral busbar in the main disconnect can't acommodate all the
wires, you'll have to buy one that will.
Also, a Square D lightning protector at Home Depot only costs about
$35..........takes about 5 minutes to install.


And I could use the Square D instead of the TWO rods, and you think that
would be better? If so, that's what I'll do.



If you want an authoritative book on the subject of grounding here's one
recommended by the IAEI (International Association of Electrical

Inspectors.
Soares Book on Grounding, 8E http://www.iaei.org/products_books.htm


I'll check it out. I can't thank you enough.




  #19   Report Post  
Mark Wilson
 
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Default Grounding Rod Info

I uploaded two images. The top image show the first box power comes into,
or the service disconnect. The bottom picture is the modern service panel
which branches off from the service disconnect.

Service Disconnect:
Does it look like this busbar will be able to support 4 outgoing conductors?
1. #4 ground going to grounding rod(s)
2. #4 ground going to water pipe
3. Big gague mesh going to service panel neutral bus bar
4. #4 ground going to service panel ground bus bar

If I can't put more than one conductor on each bolt, then I'm guessing I'll
have to upgrade. Will I need to change the whole box or can I just upgrade
the bar?

Modern Service Panel:
Some connections have actually be corrected since this picture was taken,
but please comment as-is and I'll know what to change. You'll notice that
it's upside down. This is how it was installed. The #4 ground coming from
the service disconnect enters the panel and attaches to the LEFT bus bar.
It attaches to the bus bar in the same as you would install a wire for a new
circuit. Is it correct to assume this wire should have been installed to
the heavier bolt to the lower left of the bar?

Please identify at which point the ground bus grounds to the box.

http://www.geocities.com/mydeadpresidents/index.html

I've got a new electrician coming over in a day or two. Hopefully, this
will be my last post.... thanks for your patience.





  #20   Report Post  
volts500
 
Posts: n/a
Default Grounding Rod Info

Sorry, another long post.

"Mark Wilson" wrote in message
...

Volts 500 wrote:
Ok, gas is done. On to the water ground. I don't know where your water
heater is located or if you have a water meter inside the house, but the
idea is the same as for the TV antenna run.......install a ground clamp

on
the metal hot and cold water pipes near the water heater.....then install
ground clamps on both sides of the water meter. Then (if possible) run a

#4
bare from the neutral busbar in the main diconnect, UNBROKEN, through the
ground clamps on the water heater, through the ground clamps on the water
meter,


Mark Wilson wrote:
To restate, the water heater, incoming gas line, and incoming power line
(and the service panels) are all in one corner of the basement so those

are
short and easy access. However, the water line actually enters the home
about 30 feet away, and there's one right angle turn to get there,

although
I could probably make the bend much more gradual. Because the water

meter
is located less than three feet from the point at which the the water pipe
enters the home, if I install ground clamps on both sides of the water
meter, I'm assuming I won't need to worry about another clamp "within 5
feet of where the water pipe enters the house"


Right.


Mark Wilson wrote:
. Knowing it's a 4 foot run
to the water heater and another 30 foot run to the water meter, do you

still
recommend using an UNBROKEN wire?



If you roll out the new #4 wire on the basement floor from the main
disconnect to the water meter, you can slide the wire through the lugs on
the two ground clamps for the water heater (clamps not connected to pipes
yet). Then connect the #4 to the service disconnect neutral busbar (first
box), staple the #4 on its way to the water heater, attach the clamps on the
hot and cold water pipes and tighten the lugs....then staple the #4 to the
bottom of the floor joists on its way to the water meter. When you get to
the water meter, slide on the ground clamps as you did for the water heater.
Finito.


Volts500 wrote:
and on to a point

within 5 feet of where the metal underground water pipe enters the house.
It doesn't have to be done exactly like that, but that's the way I would

do
it, if possible. At the very least an unbroken #4 must be ran from the
neutral busbar to within 5 feet of where the water pipe enters the
house.......then jumper the water meter and hot water with short pieces

if
you want.



Mark Wilson wrote:
Okay, this sounds like a good way to do it. Because using a conductor to
join the water pipe and the grounding rods OUTDOORS would be very

difficult,
is grounding the water pipe from the inside (as you describe) really an
adequate substitute?



Substitute for what? I seriously doubt that you will find an electrician
who won't run the wire on the inside of the basement from the main
disconnect to the water meter. The #4 bare wire run to the ground rods
will be totally a separate run.......they will be bonded together with the
water ground _at_ the neutral busbar in the main service disconnect (first
box). Does that answer your question?


Mark Wilson wrote:
Also, because the ground rods will be located at one
part of front yard while the water pipes enter the home about 20 yards

away,
will this be a problem having "two separate ground" locations, so to

speak?


No, they will be bonded together as mentioned above, and permitted by code.
Actually, it's the prefered method since the water ground is so far away.


Mark Wilson wrote:
I'm just going to have to get some images up for you to see.


I checked them out, thanks, pictures help a _lot_.


I've tried to
find online diagrams or descriptions of how the panelboard should looked
properly wired, but I can't find any. Let me try one more time to

describe
it. Incoming power to my house has three stranded conductors contained in
one cable. The two hot conductors are insulated and the third is bare
metal. These conductors are several times the size of a 4 gague wire,
including the bare one. Inside the main disconnect box, the two hot
conductors go to the solitary 100A Breaker. The bare metal conductor goes
to what I guess we have been calling the neutral "busbar". This little
busbar is grounded to the box itself, and from this busbar a relatively
smaller #4 wire originates and, acting as GEC, goes out to earth ground.

A
second #4 wire also originates from this bus bar and goes out to the
grounding bus bar of the panelboard (which I have been calling the modern
service panel).



OK, that part is wrong, IMO. The cable going from the main disconnect
(first box) to the "modern panelboard" should have been a 4 wire cable with
two hots, one insulated neutral and one bare equipment grounding conductor.
The neutral in the "modern panelboard" must be isolated from
ground.........once the neutral is grounded at the main disconnect (first
box) it should never be grounded again.


Mark Wilson wrote:
Leaving from the main disconnect box is a cable exactly
like the one that comes into the main disconnect box. The two hots go to
the 100A breaker IN the panelbox. The neutral goes to neutral bus bar of
the panelboard. There is no green screw that I can see, but it seems

clear
that a metal bar grounds one bus to the box itself.



You should have two buses in the "modern panelboard". One bus, the neutral,
should be _isolated_ from ground (and have only white circuit wires
connected to it). The other bus in the "modern panelboard" is the equipment
grounding bus. It should be connected to the panelboard metal enclosure and
have all of the bare and green circuit wires connected to it.


Mark Wilson wrote:
Although the electrician already said it was okay, I'll have him look at

it
again to be certain. I really am going to let him mess with it rather tha

n
doing it myself.



This is kinda turning into a mess (that's OK, I kinda figured that it would
from the time that you first posted a while back.) Before the electrician
gets started ask him how much a new service will cost. IMO, the hourly rate
that he is going to charge to fix that mess and the grounding just may come
close to the price of a new service. At least tell him that you want a
permit pulled and an inspection done for the work that he is going to do so
he'll know that he can't take any shortcuts.......and he'll have to fix
anything that he knows is wrong. Again, it may be cheaper just to tear it
all out and start over.......would only take 4 to 6 hrs. to totally rebuild
and properly ground that service (I looked at your pictures). Just keep in
mind that rebuilding a service is most likely his bread and butter
work......he'll probably have a fixed price that will not reflect an hourly
rate. Something to think about anyway.


Volts500 wrote:
OK, water ground done. On to cable TV. While you say that you won't be
using cable, now is the time to get a decent ground connection to
it.........if cable is installed later and not grounded properly, the TV,
VCR and/or cable modem, and possibly the computer will be subject to

damage.
From the outside cable TV ground block, an insulated #10 can be split
bolted to any of
the above mentioned ground wires.



Mark Wilson wrote:
I may not understand the term, but there really isn't any kind of cable
ground block outside the house. Cable runs down the house to a splitter,
then enters the house in two places. I guess I could install some kind of
"antenna discharge unit" and run a ground from there. But you're saying I
should run the #10 outside the house all the way to one of the grounding
rods? It's literally on the opposite side of the house from where the

rods
will be. It would be a very long horizontal run at best IF I dug under my
sidewalk and/or porch. If I don't go under the concrete, then I'd have

to
go along side the house and over the front door and past a few windows.

My
wife would kill me. Would it be unsafe to run the #10 ground through the
INSIDE of the house? (That's the way it is now)



The way that I would do it (since it such a long distance) is to drive a
ground rod outside where the cable enters the house......connect a #10 from
the cable ground block (look for a screw or a lug on it) to the ground
rod........then run a #6 (from the ground rod) through the inside of the
house and split-bolt it to anywhere on the GEC.....or land it on the main
disconnect (first box) neutral busbar. Since you aren't using the cable at
this time, if you can get the ground rod in and the #6 to the GEC, if/when
the cable gets hooked up, the cable people will be able to do the rest.


Volts500 wrote:
Now for the phone. The telephone primary protector should be installed
outside the house by the tele co. and attached to the bare #4 that's

coming
outside to catch the ground rod......or to the ground rod......whatever
floats your boat. This connection is best made by the tele co. people
though, if/when they come out to get the demark box right.



Mark Wilson wrote:
Ok, will do.



Volts500 wrote:
The ground conductors connecting the phone and cable ground blocks to the
grounding electrode system are usually a insulated
wire from the ground block to where they are connected to the grounding
electrode system.

Like I said, that's how I would do it. Without seeing it, that's the

best
I can do for you. Actual installation may differ somewhat, but that's

the
general idea. One thing is for sure, as slow as I type, I could have

done
had the job done for you in the same amount of time that it has took me

to
type this post.



Mark Wilson wrote:
Tell me, what DO you get out of helping out guys like me? Is is just good
samaritanism? I'm always amazed at how generous some people are with

their
knowledge and time. I really do appreciate it.



Something to do I guess. It's my way of relaxing after work too. Plus,
while I have my certification and have done my bit as a residential wireman,
I've always been a large commercial and industrial electrician. Helping
people in this NG helps me stay up with current residential wiring codes,
methods, get homeowner feedback, etc., for those times when people ask me to
do some residential wiring for them (so much for samaritanism :-). Also,
I get a lot of info from other people on unrelated topics in this NG, so
it's my way of returning the favor. Of course, a word of thanks or
appreciation goes a long way too, and for that, I thank _you_. Also, in
your case, you've been jerked around by so many so called "electricians"
that I felt you deserved some extra effort.


Volts500 wrote:
Please get it inspected by a _real_ electrical inspector.



Mark Wilson wrote:
I will Volts500. Thanks for your genuine concern.



Volts500 wrote:
If your neutral busbar in the main disconnect can't acommodate all the
wires, you'll have to buy one that will.
Also, a Square D lightning protector at Home Depot only costs about
$35..........takes about 5 minutes to install.



Mark Wilson wrote:
And I could use the Square D instead of the TWO rods, and you think that
would be better? If so, that's what I'll do.



The lightning arrestor is_not_ a replacement for the two ground rods. Since
your water ground is so far from the electric service, the two ground rods,
IMO, are a_must._ A lightning arrestor is basically useless without a good
grounding system.


Volts500 wrote:
If you want an authoritative book on the subject of grounding here's one
recommended by the IAEI (International Association of Electrical

Inspectors.
Soares Book on Grounding, 8E http://www.iaei.org/products_books.htm


If you read that book, you should have no trouble understanding the
principles and doing the work yourself.......but still get it inspected,
please. The whole job, if you do DIY and pay for a permit and inspection
(and including the price of the book) should be about $200. Just remember
that I've overkilled this deal a bit in an attempt to avoid confusion and a
lot of what ifs and why for's. If you are having trouble driving the ground
rods, rent a rotory hammer that has a chuck that is big enough to slip over
the ground rod and have at it.


Mark Wilson wrote:
I'll check it out. I can't thank you enough.



You're welcome. I hope this hasn't become too confusing.




  #21   Report Post  
volts500
 
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"'nuther Bob" wrote in message
...

I may have some issues with the depth. You hit hardpan in my yard at
6 to 8 feet deep. I don't think a copper rod will got through it,
no matter what. The stuff is like concrete, I couldn't get through
it with a steel truck bar.



Sorry, living on an overgrown sandbar, sometimes I forget how hard it is to
drive ground rods in some other parts of the country. The NEC permits a
ground rod to be driven at a 45 degree angle (no less), if that helps.


How deep does the ring have to be ? Does it really need to be a
circle ? Or could I run 20 feet along side the house in a ditch ?



2 feet deep, doesn't need to be a circle, but make it as long as you can
past the required 20 feet.....use a #2 copper.......keep the trench beyond
the roof drip line, where the soil will stay wet(er).




  #22   Report Post  
Mark or Sue
 
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"Mark Wilson" wrote in message
...
I uploaded two images. The top image show the first box power comes into,
or the service disconnect. The bottom picture is the modern service panel
which branches off from the service disconnect.

Service Disconnect:
Does it look like this busbar will be able to support 4 outgoing

conductors?
1. #4 ground going to grounding rod(s)
2. #4 ground going to water pipe
3. Big gague mesh going to service panel neutral bus bar
4. #4 ground going to service panel ground bus bar


Looks ugly. You may want to look for a normal 5 to 8 hole panel grounding
bus bar and screw it to that disconnect panel. They can usually accomodate
wires up to #4, and some will go even larger. They require a #10 threaded
hole in your chassis. If you don't have that, you can get double lugs that
bolt to the panel, but you'll need two it doesn't look like they'll fit.


If I can't put more than one conductor on each bolt, then I'm guessing

I'll
have to upgrade. Will I need to change the whole box or can I just

upgrade
the bar?


May want to buy a new disconnect. Yours looks old and it may be difficult to
now the listings for multiple wires under a screw. Getting compatible bars
may even be a problem. I bought a 3R (raintight) Cutler Hammer disconnect
that can do up to 125A for about $30 at home depot.


Modern Service Panel:
Some connections have actually be corrected since this picture was taken,
but please comment as-is and I'll know what to change. You'll notice

that
it's upside down. This is how it was installed. The #4 ground coming

from
the service disconnect enters the panel and attaches to the LEFT bus bar.
It attaches to the bus bar in the same as you would install a wire for a

new
circuit. Is it correct to assume this wire should have been installed to
the heavier bolt to the lower left of the bar?

Please identify at which point the ground bus grounds to the box.


You have more serious problems here (I think volts500 answered some of these
questions in a combined reply). You only have 3 wires, and must have 4. It
also appears that you have a mix of neutrals and grounds on each bus.
Hopefully, the neutrals are on one side and the ground on the other. If not,
you need to rearrange them so that is the case. It looks like that big
horizontal bar is connecting both your busses together. This needs to come
out if you're separating the neutral and ground (unless there is yet another
grounding bus that I don't see, but I don't know where it would fit). Then,
connect an insulated neutral to the neutral bus and a grounding wire to the
grounding bus. I'm not sure if that braided neutral counts as an insulated
neutral. You should replace that cable with SER (3 insulated, 1 braided
ground), or some other suitable wire/cable type.

Also, look for the bus that has a bonding screw into the cabinet back. This
is the bus that must be ground. The other should be insulated and will be
the neutral (hopefully, either bar can be bonded depending on which one you
put the screw in). It doesn't matter which hole the ground wire uses,
because the screws have a minimum and maximum wire limit -- just use one
that is correct for your wire (and use the correct bus).

I can't see enough to now how salvagable this is -- you may need to start
over.

--
Mark
Kent, WA



  #23   Report Post  
w_tom
 
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Code does not define how to measure resistance of earth
ground. The same application notes that demonstrate how to
install a more serious 'single point earth ground' (which is
labeled MGB in the picture):
http://www.leminstruments.com/pdf/LEGP.pdf (figure on page
14 or)

http://leminstruments.com/grounding_...ml/index.shtml
(section entitled "Measuring Ground Resistance at Cellular
Sites,Microwave and Radio Towers")

That Lem Instrument application describes measuring earth
ground resistance since that is what they are selling.

'nuther Bob wrote:
On Sat, 12 Jul 2003 19:13:36 -0400, w_tom wrote:
Code does not define how that earth resistance is to be
measured. Most locations will get less than 25 ohms with only
one ground rod.


What do you do to measure this ? Stick one lead of the meter on
the rod and another in the ground ? How far away would you put
the ground lead ?

I can see this having a serious variation in my area in the summer
dry season. The rest of the year is probably wet enough to get some
conductivity.



  #24   Report Post  
w_tom
 
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Code does not state distance to water pipe because code
addresses human safety issues. Wire length in a residence is
irrelevant for human safety. But wire longer than 10 feet has
adverse effects to earthing for surge protection. Again, code
is only concerned with wire resistance. Surge protection
worries about wire impedance which is why that wire must be
short and other requirements (no splices, no sharp bends,
etc).

Transistor safety (also known as surge protection) is beyond
scope and purpose of the NEC. After all, who creates NEC
requirements? National Fire Protection Association - because
code is written to protect human life.

But for transistor safety, that ground wire length and how
the earthing system is connected (single point earth ground)
exceeds what code requires. We must enhance an 'NEC
required' earthing system to also provide an effective 'surge
protection' earthing system.

For example, a ground wire can be grouped with other wires
to meet NEC. But for effective surge protection, that
earthing wire must be separate from other wires - so as to not
create induced surges on those other wires. Ground wire must
not be in close electromagnetic proximity with other non
earthing wires. Code does not require this because code does
not fully address surge protection issues.

Ground wire from incoming utility can connect to breaker box
ground to meet code. But for surge protection, the earthing
system must be enhanced. All earthing wires must run
independently and meet at the central earth ground - be it the
MGB, bulkhead, earthed structural member, or earth ground
rod(s). All utilities must meet at this single point ground
to upgrade an 'NEC required' earth ground into an effective
surge protection earth ground.

Other limitations. Buried ground wire may be 2 foot deep to
meet code. But for surge protection, that wire must also
remain below the frost line. Earth ground is non conductive
when frozen. Therefore many ring grounds also include 8'
earth ground rods to address problems such as deep frozen
earth and geology variations.

Sand is also a serious problem for earthing.

Halo or ring ground addresses problems beyond what code
requires; especially if in sandy soil. Since we cannot make
earth ground conductive enough, then we attempt to make earth
under the building "equipotential". But wire is not a
conductor to surges. Wire becomes an electronic component.
So we also want that ring ground to become the best conductive
earth ground in the facility - the 'single point earth
ground'. IOW ring ground enhances an NEC required earth
ground for two complementary reasons as demonstrated in that
previously cited Lem Instrument URL and in a figures from
another industry professionals:

http://www.erico.com/erico_public/pd...es/Tncr002.pdf
http://www.xantrex.com/support/docserve.asp?id=337
http://www.cinergy.com/surge/ttip08.htm


Mark or Sue wrote:
"'nuther Bob" wrote in message
...
On Sat, 12 Jul 2003 03:22:50 GMT, "Mark or Sue"
wrote:
To summarize, if you have a metal water pipe that is in contact
with the earth for 10 feet or more, you MUST use it as your
primary grounding electrode.


WOuld "MUST" still apply if the proper attachment location to the
water pipe is 35 feet from the panel ? Or would the code then
prefer two grounding rods ?

Bob


Code says "must", but is silent on the distance from the panel.
You have to run a wire to the pipes anyway (whether outside pipes
are metal or plastic), the wire is just larger when it is your
GEC. So you can't skip this part.



  #25   Report Post  
Mark Wilson
 
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Volts500, Mark and Sue,

Thanks to your help and the help of others I now feel I know enough to keep
the electrician honest. I've got the soars book on order and I plan to do
some of the grunt work myself. I honestly didn't realize this thread would
get so involved. It's very kind of you to help out while keeping the focus
on my safety. To ease my guilt at having imposed on so much of your time, I
can only hope others will get some use out of it as well.

Keeping everything in mind, I'm going to follow Volt's advice for all the
grounding. I'm also going to replace the Service Disconnect (as Mark
suggested), and rewire the panelboard. Now, this opens up a few more
questions. If I had any shame, I would feel too guilty to ask any more, but
I guess I'm a bit shameless. If you guys would start giving crappy and
vague advice, you really would avoid people like me buggying you so much.

Volts: It appears that the metal housing of the water meter negates the
need to jumper it. In this case, I think it would be better to simply
attach the grounding clamp as near as possible to the point at which the
pipe enters the home. Agreed? (See image)
http://www.geocities.com/mydeadpresidents/index.html

As for outgoing circuits, what kind of trouble can be caused by having a mix
of neutrals and grounds on each bus? I'm gonna fix it no matter what, but
it won't be the first thing I do.

You've seen my Service Disconnect box. Is it common to have a separate
service disconnect box as I do? Had it been wired correctly, couldn't I
have just used the panelboard which has it's own 100 AMP breaker) and then
skip the current Service Disconnect box?

Tell me I have this right. Let's assume I keep the Service Disconnect at
100 AMP but I want to upgrade the box. I would then get a new box (that
supports at least 100amps) then add a 100 AMP breaker for the incoming power
and then get another 100 AMP breaker for the power outgoing to the
panelboard. In other words, because my panelboard has room for the circuits
I need and that I forsee needing, I see no reason to try to run circuits
from my new Service Disconnect box and therfore, the power should just go
straight through. Put another way, I'm not using the panelboard as a
subpanel in the traditonal sense. I'm using the panelboard for ALL circuits
and the Service Disconnect is really nothing more than a way to kill the
main power and provide a lauching point for grouding conductors. Is there
anything wrong with this setup?

My main service breaker only allows for 100amps. I've read that a 100
breaker usually means you can go 200 or more, but I've totaled up the amps
of the circuits in my panel box and it's around 500! However, in the two
years I've lived here, I've never once thrown a breaker. Also, some of the
circuits are used seasonally. I've got 60 amps dedicated to the AC, but I
also have 160 amps dedicated to space heaters which I almost never use, not
even in the winter time (because that same room also has a wood stove). Is
it time to upgrade to 200amps?

I regards to power coming into my home (2 hot/1 neutral), how much power is
available? I mean, right now, judging by the breaker in my Service
Disconnect, I'm utilizing up to 100 AMPs of power. If I wanted to go 200,
then can I just upgrade to a breaker and panel that support the extra amps?
Or, is there some kind of physical change the Power Co will have to make?

Thanks










  #26   Report Post  
Mark or Sue
 
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"Mark Wilson" wrote in message
...
Volts500, Mark and Sue,

Thanks to your help and the help of others I now feel I know enough to

keep
the electrician honest. I've got the soars book on order and I plan to

do
some of the grunt work myself. I honestly didn't realize this thread

would
get so involved. It's very kind of you to help out while keeping the

focus
on my safety. To ease my guilt at having imposed on so much of your time,

I
can only hope others will get some use out of it as well.

Keeping everything in mind, I'm going to follow Volt's advice for all the
grounding. I'm also going to replace the Service Disconnect (as Mark
suggested), and rewire the panelboard. Now, this opens up a few more
questions. If I had any shame, I would feel too guilty to ask any more,

but
I guess I'm a bit shameless. If you guys would start giving crappy and
vague advice, you really would avoid people like me buggying you so much.



Don't feel guilty -- that what these forums are for. If we get tired of your
questions, you'll only get lame (or no) answers.


Volts: It appears that the metal housing of the water meter negates the
need to jumper it. In this case, I think it would be better to simply
attach the grounding clamp as near as possible to the point at which the
pipe enters the home. Agreed? (See image)
http://www.geocities.com/mydeadpresidents/index.html

As for outgoing circuits, what kind of trouble can be caused by having a

mix
of neutrals and grounds on each bus? I'm gonna fix it no matter what, but
it won't be the first thing I do.


If it is service equipment, then none as ground and neutral are the same. In
a subpanel, the voltage drop across the neutral will raise your ground this
same amount (typically 1 to 3 volts). For things that actually go to a true
ground, such as audio tuners and cable TV cables, you'll get a current
flowing in the shield causing noise, hum, or other interesting behavior.


You've seen my Service Disconnect box. Is it common to have a separate
service disconnect box as I do? Had it been wired correctly, couldn't I
have just used the panelboard which has it's own 100 AMP breaker) and then
skip the current Service Disconnect box?


This seems to be a regional thing. Some areas demand an outside disconnect.
Where I live, the disconnects can be inside the house as long as they are
very near where the service cables enter. Since your second panel is also
outside, you meet the outside disconnect rule. The only other issue would be
if your area has a limitation on how far the main disconnect needs to be
from the meter. If they have one, it may be short, like 5 feet. The intent
here is to minimize the length of unfused service conductors and the amount
of structure they will damage should they flame up.


Tell me I have this right. Let's assume I keep the Service Disconnect at
100 AMP but I want to upgrade the box. I would then get a new box (that
supports at least 100amps) then add a 100 AMP breaker for the incoming

power
and then get another 100 AMP breaker for the power outgoing to the
panelboard. In other words, because my panelboard has room for the

circuits
I need and that I forsee needing, I see no reason to try to run circuits
from my new Service Disconnect box and therfore, the power should just go
straight through. Put another way, I'm not using the panelboard as a
subpanel in the traditonal sense. I'm using the panelboard for ALL

circuits
and the Service Disconnect is really nothing more than a way to kill the
main power and provide a lauching point for grouding conductors. Is

there
anything wrong with this setup?


The first panel is still your service disconnect because it has a breaker in
it. Additional service rated panels must be grouped (can't be 20 feet across
the wall) and there is usually no fusing between them. If your local
inspector says its OK, you may be able to replace the 100A disconnect with
just a junction box if the existing house circuit panel has a 100A main
disconnect. Then run new wires from the meter base to the panel where all
your circuits are and use it as a main service rated panel.


My main service breaker only allows for 100amps. I've read that a 100
breaker usually means you can go 200 or more, but I've totaled up the amps
of the circuits in my panel box and it's around 500! However, in the two
years I've lived here, I've never once thrown a breaker. Also, some of

the
circuits are used seasonally. I've got 60 amps dedicated to the AC, but I
also have 160 amps dedicated to space heaters which I almost never use,

not
even in the winter time (because that same room also has a wood stove).

Is
it time to upgrade to 200amps?


Again a local thing. Here, all services must be wired for 200A, but you
could put in a 100A breakered panel if you want to. The wires will have to
be sized for 200A though. If your service wires are 100A, then you can't
increase to 200A without replacing them. Same with your meter base -- is it
100A or 200A? You can put a 200A breakered panel on a 100A service if you've
done a load calculation and it indicates you're not exceeding the 100A
service. Finally, check with your utility to see how big your transformer
is. You'll want at least a 20 KVA for a 200A service, and preferably a 25 or
30 KVA.


I regards to power coming into my home (2 hot/1 neutral), how much power

is
available? I mean, right now, judging by the breaker in my Service
Disconnect, I'm utilizing up to 100 AMPs of power. If I wanted to go 200,
then can I just upgrade to a breaker and panel that support the extra

amps?
Or, is there some kind of physical change the Power Co will have to make?


100A is available at 240V (24 KVA). Power company may have to increase their
wires to you and may have to increase the transformer. You may have to
increase the meter base, the service entrance wires and the main panel.

--
Mark
Kent, WA



  #27   Report Post  
volts500
 
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"Mark Wilson" wrote in message
...

Volts: It appears that the metal housing of the water meter negates the
need to jumper it. In this case, I think it would be better to simply
attach the grounding clamp as near as possible to the point at which the
pipe enters the home. Agreed? (See image)
http://www.geocities.com/mydeadpresidents/index.html



Now we're getting into the what if's and why for's (Although you seem to be
grasping the concepts, I'm trying to avoid all of that to keep
misunderstandings to a minimum.) Best to jumper the meter and be done with
it.......$2 part, 5 min. work, tops. Don't forget to jumper the hot water
to the cold water at the water meter.


As for outgoing circuits, what kind of trouble can be caused by having a

mix
of neutrals and grounds on each bus? I'm gonna fix it no matter what, but
it won't be the first thing I do.



Can cause all sorts of nasty problems. I think Mark covered that and the
rest of it pretty well.




  #28   Report Post  
Gary Slusser
 
Posts: n/a
Default Grounding Rod Info


"volts500" wrote

"Mark Wilson" wrote in message
...

Volts: It appears that the metal housing of the water meter negates

the
need to jumper it. In this case, I think it would be better to

simply
attach the grounding clamp as near as possible to the point at which

the
pipe enters the home. Agreed? (See image)
http://www.geocities.com/mydeadpresidents/index.html



Now we're getting into the what if's and why for's (Although you seem

to be
grasping the concepts, I'm trying to avoid all of that to keep
misunderstandings to a minimum.) Best to jumper the meter and be done

with
it.......$2 part, 5 min. work, tops. Don't forget to jumper the hot

water
to the cold water at the water meter.


As for outgoing circuits, what kind of trouble can be caused by

having a
mix
of neutrals and grounds on each bus? I'm gonna fix it no matter

what, but
it won't be the first thing I do.



Can cause all sorts of nasty problems. I think Mark covered that and

the
rest of it pretty well.


Most water meters that I'm familiar with use rubber compression or
washer type seals. Those big brass nuts, they really don't connect
electrically to the tubing to the meter body all that well.

Gary
Quality Water Associates


  #29   Report Post  
Mark Wilson
 
Posts: n/a
Default Grounding Rod Info

Mark,


You've seen my Service Disconnect box. Is it common to have a separate
service disconnect box as I do? Had it been wired correctly, couldn't I
have just used the panelboard which has it's own 100 AMP breaker) and

then
skip the current Service Disconnect box?


This seems to be a regional thing. Some areas demand an outside disconnect.
Where I live, the disconnects can be inside the house as long as they are
very near where the service cables enter. Since your second panel is also
outside, you meet the outside disconnect rule. The only other issue would

be
if your area has a limitation on how far the main disconnect needs to be
from the meter. If they have one, it may be short, like 5 feet. The intent
here is to minimize the length of unfused service conductors and the amount
of structure they will damage should they flame up.


Actually, both my Service Disconnect and Panelboard are inside the house.
Outside the house there is only a meter. All in all, having a separate
Service Disconnect is fine for now, although I think I'll replace it with
the Cutler Hammer box you suggested. Of course the Power Co will have to
someone disconnect power for the Service Disconnect to be rewired. How does
the Power Co go about shutting down power? Do they have to climb the pole
or is there something they can do at the meter?

My main service breaker only allows for 100amps. I've read that a 100
breaker usually means you can go 200 or more, but I've totaled up the

amps
of the circuits in my panel box and it's around 500! However, in the two
years I've lived here, I've never once thrown a breaker. Also, some of

the
circuits are used seasonally. I've got 60 amps dedicated to the AC, but

I
also have 160 amps dedicated to space heaters which I almost never use,

not
even in the winter time (because that same room also has a wood stove).

Is
it time to upgrade to 200amps?


Again a local thing. Here, all services must be wired for 200A, but you
could put in a 100A breakered panel if you want to. The wires will have to
be sized for 200A though. If your service wires are 100A, then you can't
increase to 200A without replacing them. Same with your meter base -- is it
100A or 200A? You can put a 200A breakered panel on a 100A service if

you've
done a load calculation and it indicates you're not exceeding the 100A
service. Finally, check with your utility to see how big your transformer
is. You'll want at least a 20 KVA for a 200A service, and preferably a 25

or
30 KVA.


The meter says something like "200cl 240v 3w" I'll give the Power Co a call
and look into it. I'm sure it's not a black and white issue, but if I'm not
throwing breakers, is it fair to say I don't really need 200A at this time?
I hate to rewire everything only to decide later that I need to upgrade the
panelboard too.






  #30   Report Post  
Mark Wilson
 
Posts: n/a
Default Grounding Rod Info

Volts,

I'll go ahead and jumper that water meter as you said. Regarding the ground
wire going from netural bar to water heater over to water meter.... While
trying not to make dramtic bends in the conductor, it's going to be almost
impossible to prevent the it from contacting the metal ducts and armored
cable that run along the ceiling. I suppose I could try to insulate the
wire somehow when it gets near the AC, or perhaps I can find some insulated
green #4 (afterall, this is being used inside anyway). Does contact with
the ducts or AC create a problem? About how much bend can a ground wire
take (and still function well)? 135 degrees?






  #31   Report Post  
Mark or Sue
 
Posts: n/a
Default Grounding Rod Info

"Mark Wilson" wrote in message
...
Actually, both my Service Disconnect and Panelboard are inside the house.
Outside the house there is only a meter. All in all, having a separate
Service Disconnect is fine for now, although I think I'll replace it with
the Cutler Hammer box you suggested. Of course the Power Co will have to
someone disconnect power for the Service Disconnect to be rewired. How

does
the Power Co go about shutting down power? Do they have to climb the pole
or is there something they can do at the meter?


Ah, now were making progress. Inside the house, they want your main
disconnect as soon as possible. Usually, this means within 5' of where the
wire penetrates the exterior wall. If your service panel is 20 feet from the
disconnect, that explains why you have a disconnect. Why they didn't put a
normal panelboard where the disconnect is located I don't know....

Usually, power is disconnected by pulling the meter. Sometimes, you can do
this yourself, but you must inform the power company so they can come back
and seal it (and know why the seal has been broken). It would be better to
have the power company come pull your meter, as they can deal with any
oh-****s that happen. A service enclosure is not a nice place to have things
stuck or falling out! The only thing that sucks here is re-establishing
service. You may be without power for a day while you wait for the power
company to come back. You may feel more comfortable putting the meter back
in than taking it out. That would get you going again sooner.

Climbing the pole would work too, but they'll only do that if you need to
work in or replace the meter enclosure.


The meter says something like "200cl 240v 3w" I'll give the Power Co a

call
and look into it. I'm sure it's not a black and white issue, but if I'm

not
throwing breakers, is it fair to say I don't really need 200A at this

time?
I hate to rewire everything only to decide later that I need to upgrade

the
panelboard too.


That would be a Class 200 meter for normal 240/120 household service. You
probably have a 200A meter enclosure if you have a 200A meter, so perhaps
this part can stay forever (unless its deteriorated). Yes, if that main is
not tripping you're probably OK (unless that breaker is defective). However,
you may want to measure your voltage sometime when you're pushing things and
see how much it sags. A wimpy transformer will help prevent you blowing the
breaker. I think that is why my power company uses a transformer that is
about half the size of your needs. When you really need 100A, you're going
to have a fair amount of voltage drop and may not get to drawing 100A
because things are drawing less current at the lower voltage.

Finally, just because you have a 200A meter doesn't mean you had 200A
service entrance conductors installed. If you ever decide to upgrade the
main disconnect to 200A, you'll need to check the wires to the meter and
from the meter for proper size. You can defer that task if you just replace
the 100A disconect with another 100A unit.

--
Mark
Kent, WA



  #32   Report Post  
Mark or Sue
 
Posts: n/a
Default Grounding Rod Info

"Mark Wilson" wrote in message
...
Actually, both my Service Disconnect and Panelboard are inside the house.
Outside the house there is only a meter. All in all, having a separate
Service Disconnect is fine for now, although I think I'll replace it with
the Cutler Hammer box you suggested. Of course the Power Co will have to
someone disconnect power for the Service Disconnect to be rewired. How

does
the Power Co go about shutting down power? Do they have to climb the pole
or is there something they can do at the meter?


Ah, now were making progress. Inside the house, they want your main
disconnect as soon as possible. Usually, this means within 5' of where the
wire penetrates the exterior wall. If your service panel is 20 feet from the
disconnect, that explains why you have a disconnect. Why they didn't put a
normal panelboard where the disconnect is located I don't know....

Usually, power is disconnected by pulling the meter. Sometimes, you can do
this yourself, but you must inform the power company so they can come back
and seal it (and know why the seal has been broken). It would be better to
have the power company come pull your meter, as they can deal with any
oh-****s that happen. A service enclosure is not a nice place to have things
stuck or falling out! The only thing that sucks here is re-establishing
service. You may be without power for a day while you wait for the power
company to come back. You may feel more comfortable putting the meter back
in than taking it out. That would get you going again sooner.

Climbing the pole would work too, but they'll only do that if you need to
work in or replace the meter enclosure.


The meter says something like "200cl 240v 3w" I'll give the Power Co a

call
and look into it. I'm sure it's not a black and white issue, but if I'm

not
throwing breakers, is it fair to say I don't really need 200A at this

time?
I hate to rewire everything only to decide later that I need to upgrade

the
panelboard too.


That would be a Class 200 meter for normal 240/120 household service. You
probably have a 200A meter enclosure if you have a 200A meter, so perhaps
this part can stay forever (unless its deteriorated). Yes, if that main is
not tripping you're probably OK (unless that breaker is defective). However,
you may want to measure your voltage sometime when you're pushing things and
see how much it sags. A wimpy transformer will help prevent you blowing the
breaker. I think that is why my power company uses a transformer that is
about half the size of your needs. When you really need 100A, you're going
to have a fair amount of voltage drop and may not get to drawing 100A
because things are drawing less current at the lower voltage.

Finally, just because you have a 200A meter doesn't mean you had 200A
service entrance conductors installed. If you ever decide to upgrade the
main disconnect to 200A, you'll need to check the wires to the meter and
from the meter for proper size. You can defer that task if you just replace
the 100A disconect with another 100A unit.

--
Mark
Kent, WA



  #33   Report Post  
Mark or Sue
 
Posts: n/a
Default Neutral vs. Ground - was Grounding Rod Info

"'nuther Bob" wrote in message
...
If you only have a service panel - as in the meter is on a box and
direct wired to a 100A breaker in the service panel - are there rules
about separating ground and neutral ? In my box, it's all one bus bar.
I also have a subpanel off the main panel - do the rules change when
we get into the subpanel ?


Yes. At the service, where you have the meter and main breaker, this is your
Service Disconnect and it is where your "Service" stops. This is the last
place that neutral and ground are connected together. If you have another
panel in the house, this is a subpanel and it must have a 4 wire feeder and
the neutral and ground busses must be isolated. Only the grounding bus may
be electrically connected to the panel enclosure in a subpanel.

There is an exception to this for a panels at detached buildings, but there
must be no electrically conductive path between the service equipment and
the remote panelboards (ecxcept for the service feeder itself). Typical
connections that would mandate a 4 wire feeder to a remote building --
grounded phone or CATV wires, or metal water, gas, or oil pipes. I also
think that mobile homes must have a 4 wire feeder from the typically yard
mounted pole/disconnect.

The idiot that did my house ran a 3-wire feeder to the pool shed (which
because its a pool is not allowed), but there is an oil pipe in there and
another one in the house. The oil pipe was a parallel neutral back to the
panel. Thankfully, this pipe was not loose or arcing in the oil tank!

--
Mark
Kent, WA



  #35   Report Post  
Mark or Sue
 
Posts: n/a
Default Neutral vs. Ground - was Grounding Rod Info

"'nuther Bob" wrote in message
...
On Thu, 17 Jul 2003 03:36:19 GMT, "Mark or Sue"
wrote:
Yes. At the service, where you have the meter and main breaker, this is

your
Service Disconnect and it is where your "Service" stops. This is the last
place that neutral and ground are connected together. If you have another
panel in the house,


If the second panel is physically connected to the main panel via a
1.5" coupling, is it still a "sub panel" and is it a source of
concern ?


This coupling is equivalent to the equipment grounding wire, and may even
replace the equipment grounding wire if the conduit is hard metal (not flex)
and effectively bonded to the service panel or neutral. If these two panels
are side by side, then I'm not sure if you're allowed to have it be a second
service panel or not. You definitely could if the meter was double lugged
and a service conductor went to each. If a breaker in the first panel is
feeding the second panel a few inches away, I'm not sure if that forces it
to be a subpanel or not...I'm leaning towards it having to be a subpanel,
but I can't prove my case.

If this second panel must be a subpanel, then in it you'd need a grounding
bus that is bonded to the 1.5" conduit and the neutral bus would have to be
insulated from the panel chassis.

--
Mark
Kent, WA





  #36   Report Post  
Mark Wilson
 
Posts: n/a
Default Grounding Rod Info

Mark,

"Mark Wilson" wrote in message
...
"Mark Wilson" wrote in message

What you say makes sense, but the cable makes it to the Service

Disconnect
within 3 feet of entering the building, and the panelboard is right next

to
it. I'm pretty sure the "electrician" (and I use that term lightly.. he

he)
just didn't want to mess with shutting power off at the meter or having

to
call the Power Co. Plus, he wouldn't have to rewire as much.

Because the panelboard also has it's own 100A breaker (which has never

been
thrown) I'm even more likely to believe things are okay for now.


With what you've said now, your panels are OK. Both are service rated
panels, and you have two disconnects. One of those disconnects is not

really
needed and could be removed. Or, perhaps replace it with a 100A transfer
switch if you've thought about generator power...


oh no, not another tangent... lol. (generator) I was wrong about the
panelboard. It's actually rated at 200A and the breaker is 200, not 100.
I'm still considering an upgrade to 200A. Because the panelboard is rated
for 200, if I upgrade to 200, I could skip the first disconnect which might
be the cost effective way to go. This would mean about a 5 foot run from
the outside meter to the panelboard. If I did this, I'm guessing I'd just
run all my GEC and other grounds from the ground bus bar. I might check
back with you guys on a few things, but I've got enough to get to work now
and I think I'll let this thread die.

Oh, but I am still wondering about that ground conductor going from the
Service Disconnect to my water meter and pipe (from the inside of the
house). Is it bad for the bare conductor to contact armored cable (bx) or
metal duct work? Knowing the answer will make a big difference in the
amount of work I have to do to run the wire.

Thanks for all your help and advice.


  #37   Report Post  
Mark or Sue
 
Posts: n/a
Default Grounding Rod Info


"Mark Wilson" wrote in message
...
"Mark Wilson" wrote in message
...
With what you've said now, your panels are OK. Both are service rated
panels, and you have two disconnects. One of those disconnects is not

really
needed and could be removed. Or, perhaps replace it with a 100A transfer
switch if you've thought about generator power...


oh no, not another tangent... lol. (generator) I was wrong about the
panelboard. It's actually rated at 200A and the breaker is 200, not 100.
I'm still considering an upgrade to 200A. Because the panelboard is rated
for 200, if I upgrade to 200, I could skip the first disconnect which

might
be the cost effective way to go. This would mean about a 5 foot run from
the outside meter to the panelboard. If I did this, I'm guessing I'd

just
run all my GEC and other grounds from the ground bus bar. I might check
back with you guys on a few things, but I've got enough to get to work now
and I think I'll let this thread die.


So your 100A disconnect is required. A single disconnect can not be greater
than the size of the service, so a 100A breaker had to be placed in front of
the 200A panel main. And right again, if you upgrade to 200, just remove
that 100A disconnect box and go straight to the 200A panel you already have.



Oh, but I am still wondering about that ground conductor going from the
Service Disconnect to my water meter and pipe (from the inside of the
house). Is it bad for the bare conductor to contact armored cable (bx) or
metal duct work? Knowing the answer will make a big difference in the
amount of work I have to do to run the wire.


No, it is not bad. Those things should already be grounded by the circuit
that feeds them. Those items touching the GEC won't change anything. If you
just don't like doing that, you can run insulated wire, but you'll need to
color it green (use tape or paint) where it is exposed. If you're planning
on a 200A upgrade at some point, run a #4 copper GEC to the water pipe.
Otherwise, you'll need to upsize it when you upgrade the service.

--
Mark
Kent, WA



  #38   Report Post  
Mark Wilson
 
Posts: n/a
Default Grounding Rod Info




"Mark Wilson" wrote in message
...
"Mark Wilson" wrote in message
...
With what you've said now, your panels are OK. Both are service rated
panels, and you have two disconnects. One of those disconnects is not

really
needed and could be removed. Or, perhaps replace it with a 100A transfer
switch if you've thought about generator power...


oh no, not another tangent... lol. (generator) I was wrong about the
panelboard. It's actually rated at 200A and the breaker is 200, not 100.
I'm still considering an upgrade to 200A. Because the panelboard is rated
for 200, if I upgrade to 200, I could skip the first disconnect which

might
be the cost effective way to go. This would mean about a 5 foot run from
the outside meter to the panelboard. If I did this, I'm guessing I'd

just
run all my GEC and other grounds from the ground bus bar. I might check
back with you guys on a few things, but I've got enough to get to work

now
and I think I'll let this thread die.


So your 100A disconnect is required. A single disconnect can not be greater
than the size of the service, so a 100A breaker had to be placed in front

of
the 200A panel main. And right again, if you upgrade to 200, just remove
that 100A disconnect box and go straight to the 200A panel you already

have.

understood.




Oh, but I am still wondering about that ground conductor going from the
Service Disconnect to my water meter and pipe (from the inside of the
house). Is it bad for the bare conductor to contact armored cable (bx)

or
metal duct work? Knowing the answer will make a big difference in the
amount of work I have to do to run the wire.


No, it is not bad. Those things should already be grounded by the circuit
that feeds them. Those items touching the GEC won't change anything. If you
just don't like doing that, you can run insulated wire, but you'll need to
color it green (use tape or paint) where it is exposed. If you're planning
on a 200A upgrade at some point, run a #4 copper GEC to the water pipe.
Otherwise, you'll need to upsize it when you upgrade the service.


In my case it will be MUCH easier if I don't have to worry about the GEC
touching the ducts.


--
Mark
Kent, WA


That's it for me on this thread. Thanks!


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