I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug, and the bare wire ground to the box 1st and then to
the ground on the outlet. The white wire is capped off and not being
used. When I plug in the heater it will not turn on. Breaker does not
trip.

I get 120v on each side of the plug with my voltmeter. I even was able
to test the voltage in the heater and there is 120v going to each input
inside the heater. I replaced the heater with a brand new one, and
also replace the outlet and get the same results.

Any ideas what I am doing wrong?

Thanks in advance.

wrote:
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug...

I get 120v on each side of the plug with my voltmeter.

Do you get 240V between the hots on the plug?

Chris

Check for continuity of the ground wire from the plug all the way back
to the panel ground.

Kindest Regards
Steve


On 16 Oct 2006 21:58:29 -0700, wrote:

I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug, and the bare wire ground to the box 1st and then to
the ground on the outlet. The white wire is capped off and not being
used. When I plug in the heater it will not turn on. Breaker does not
trip.

I get 120v on each side of the plug with my voltmeter. I even was able
to test the voltage in the heater and there is 120v going to each input
inside the heater. I replaced the heater with a brand new one, and
also replace the outlet and get the same results.

Any ideas what I am doing wrong?

Thanks in advance.

uh? just the red & black? Where's the nuetral connected? You gotta
have a return circuit.
if you've got 10/3 then you've to red, black, white, ground right?
Am I missing something here or just don't know what I'm talking about.

Troy


Chris Friesen wrote:
wrote:
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug...

I get 120v on each side of the plug with my voltmeter.

Do you get 240V between the hots on the plug?

Chris

"Troy" wrote in message
...
uh? just the red & black? Where's the nuetral connected? You gotta
have a return circuit.
if you've got 10/3 then you've to red, black, white, ground right?
Am I missing something here or just don't know what I'm talking about.


The latter in this case Troy. 220v does not use a neutral.

--

-Mike-

wrote in message
oups.com...
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug, and the bare wire ground to the box 1st and then to
the ground on the outlet. The white wire is capped off and not being
used. When I plug in the heater it will not turn on. Breaker does not
trip.

I get 120v on each side of the plug with my voltmeter. I even was able
to test the voltage in the heater and there is 120v going to each input
inside the heater. I replaced the heater with a brand new one, and
also replace the outlet and get the same results.

Any ideas what I am doing wrong?


Did you install a thermostat?

--

-Mike-

In article , Troy wrote:
uh? just the red & black? Where's the nuetral connected? You gotta
have a return circuit.

No, he doesn't. 240V circuits don't use a neutral.

if you've got 10/3 then you've to red, black, white, ground right?

True. Doesn't mean you have to connect them all, though.

Am I missing something here or just don't know what I'm talking about.

One or the other... maybe both.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article , Steve wrote:
Check for continuity of the ground wire from the plug all the way back
to the panel ground.

That's not the problem. If it's wired correctly (and as he describes it, it
is) the unit will work without the ground at all. Won't be safe, but it will
work.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article .com, wrote:
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3

Could've used 10/2, since it's a pure 240V load, but that's just FYI, and
unrelated to the problem.

wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug, and the bare wire ground to the box 1st and then to
the ground on the outlet. The white wire is capped off and not being
used. When I plug in the heater it will not turn on. Breaker does not
trip.

I get 120v on each side of the plug with my voltmeter. I even was able
to test the voltage in the heater and there is 120v going to each input
inside the heater. I replaced the heater with a brand new one, and
also replace the outlet and get the same results.

What do you get between the two hot legs? Here's my guess: measure that at
the outlet, and you'll see ZERO.

Possible explanations:

1) You don't have the breaker for this circuit wired correctly. I doubt that's
the case, though, since you seem to have done everything else right.

2) I've heard of, but never actually seen, panels in which adjacent lugs are
on the *same* leg of the service, instead of on opposite legs (opposite legs
being on opposite sides). You may have such a panel. But I doubt it. If they
exist at all, I'm sure they're very rare.

3) You said you installed the new breaker in a subpanel. Have you verified
that there's actually 240V coming into the subpanel? I bet there's not. Put a
voltmeter across the two main breakers (or lugs) in the subpanel, and you'll
probably see 0V. I suspect that the subpanel is wired incorrectly at the main
panel, and nobody ever noticed before because nobody ever installed a 240V
circuit in the sub before.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

wrote in message
oups.com...
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel,

Some panels will only accept 2 pole breakers in certain slots. I haven't
looked into why that is, but maybe because of this.
Look to see if your box has such a condition, and if you are doing it
properly.

On Oct 17, 12:58 am, wrote:
I can't figure out what I'm doing wrong.

The crew has given you good suggestions. Please keep us informed when
you discover what the problem was. It helps us with other questions.

thanks,

r

"Tim" wrote in message
...

wrote in message
oups.com...
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel,

Some panels will only accept 2 pole breakers in certain slots. I haven't
looked into why that is, but maybe because of this.
Look to see if your box has such a condition, and if you are doing it
properly.



I've encountered this as well. Look closely at the buss bar in the center
of the box and make sure that your 220v breaker is really connecting to
alternating buss lugs. Some boxes only have 220v capability on the first
few lugs of the buss bar and then everything below that point is 110v.

--

-Mike-

On Oct 17, 9:32 am, "Mike Marlow" wrote:
Some boxes only have 220v capability on the first
few lugs of the buss bar and then everything below that point is 110v.

Yup, a substation of mine is like that. You get 110v on each leg, and
0v across both *S*... a WTF moment.

r

wrote in message
oups.com...
I can't figure out what I'm doing wrong. I'm currently trying to add
an oulet for 4800 watt construction heater in my shop. I've run 10/3
wire to the outlet, added a 2-pole 30amp breaker to the sub-panel, and
installed a 6-30 plug by connecting the black and red wires to the
blades on the plug, and the bare wire ground to the box 1st and then to
the ground on the outlet. The white wire is capped off and not being
used. When I plug in the heater it will not turn on. Breaker does not
trip.

I get 120v on each side of the plug with my voltmeter. I even was able
to test the voltage in the heater and there is 120v going to each input
inside the heater. I replaced the heater with a brand new one, and
also replace the outlet and get the same results.

Any ideas what I am doing wrong?

Thanks in advance.

Sounds like you are measuring from each leg to ground. Measure the voltage
across the red and black wire. It should be 240 volts. If it is 0 or 120,
check back at the breaker panel. Something is miswired.
-S

Thanks for all your help!

When I get home tonight I'll check the voltage accross for 240v. I
didn't do that. At the main panel I connected the black and red to the
2 pole breaker, ground to ground bus, and white to the neutral bus (not
used). I'm thinking I'll find that I don't have 220v. The sub-panel
is not bonded. Could that have anything to do with it? How will I
know where in the panel I can add 220v breakers and where I can't?

I used the 10/3 so that I can change the configuration should my needs
change in the future.

Forgot to mention. The main panel is a Siemens EQ Load center and the
sub is also a Siemens.

Thanks

Actually the sub-panel is a Stab-Lock.

Thanks

In article . com, wrote:
Thanks for all your help!

When I get home tonight I'll check the voltage accross for 240v. I
didn't do that. At the main panel I connected the black and red to the
2 pole breaker, ground to ground bus, and white to the neutral bus (not
used). I'm thinking I'll find that I don't have 220v. The sub-panel
is not bonded.

By which you mean, I hope, that the ground and neutral busses in the subpanel
are not bonded to each other. It's *supposed* to be that way. The *only* place
where they are ever bonded together is in the service entrance panel.

Could that have anything to do with it?

No. The neutral isn't used at all in a pure 240V circuit (and can be omitted
altogether), and the ground isn't used except in the case of a ground fault in
the equipment (i.e. in normal operation, the ground isn't used either). So
nothing involving either the ground or the neutral would have any effect on
the problem you're seeing.

How will I
know where in the panel I can add 220v breakers and where I can't?

In *most* panels, any place that you can put a double-pole breaker will give
you 240V. Your panel may be an exception, as at least a couple of us have
noted, and the easiest way to tell where you can and can't is to look at the
label on the inside of the panel cover -- that will show the possible
configurations. Another way to tell is to probe between the lug screws on
adjacent breakers (with the breakers on) to see where you measure 240V and
where you get only 120V. Yet another way is to pull the breakers, and look at
the configuration of the bus bars.

But before you do any of that, the *first* thing you should do, in my opinion,
is to measure the voltage between the two main breakers (or lugs) in the
subpanel, and see whether you get 240V or 0V. I think you'll see 0V, because
- assuming that you've described everything accurately - the simplest
explanation for the problem you're seeing is that the subpanel is not wired
correctly at the main. Specifically, I think that if you look in the main
panel at the wires feeding the subpanel, you'll find that when the subpanel
was installed, the black and red wires feeding it were connected to two
separate single-pole breakers (instead of to one double-pole breaker), and
those two breakers are on the same leg of the service.

I used the 10/3 so that I can change the configuration should my needs
change in the future.

That's fine -- just wasn't necessary for *this* application. But planning for
the future is always good. :-)

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?
240v comes in and in the main service panel I know the nuetral and
ground are bonded.... never have understood that one. then each leg of
the 240v is one side of the bus bar array in the service panel.
So what am I missing? I'm asking in all seriousness. I "added" a 220
outlet for my wife one day so she could have an electric stove and I
popped the breaker immeaditly when I fired it up because of the nuetral
being tied to ground. So I shrugged said I don't get why its doing
that, read the directions with the receptacle and removed the nuetral.
All was well. I look at my dryer cord and its got 3 wires. I know the
top angled two are "hot" 120vac each and the other is the ground.
I realize that we can take a +12vdc and a -12vdc circuit and using only
2 wires get +24vdc across them and then have to have a chassis ground.
Man its been a long time since I studied electronics!

Troy

Doug Miller wrote:
In article . com, wrote:


By which you mean, I hope, that the ground and neutral busses in the subpanel
are not bonded to each other. It's *supposed* to be that way. The *only* place
where they are ever bonded together is in the service entrance panel.



No. The neutral isn't used at all in a pure 240V circuit (and can be omitted
altogether), and the ground isn't used except in the case of a ground fault in
the equipment (i.e. in normal operation, the ground isn't used either). So
nothing involving either the ground or the neutral would have any effect on
the problem you're seeing.



In *most* panels, any place that you can put a double-pole breaker will give
you 240V. Your panel may be an exception, as at least a couple of us have
noted, and the easiest way to tell where you can and can't is to look at the
label on the inside of the panel cover -- that will show the possible
configurations. Another way to tell is to probe between the lug screws on
adjacent breakers (with the breakers on) to see where you measure 240V and
where you get only 120V. Yet another way is to pull the breakers, and look at
the configuration of the bus bars.

But before you do any of that, the *first* thing you should do, in my opinion,
is to measure the voltage between the two main breakers (or lugs) in the
subpanel, and see whether you get 240V or 0V. I think you'll see 0V, because
- assuming that you've described everything accurately - the simplest
explanation for the problem you're seeing is that the subpanel is not wired
correctly at the main. Specifically, I think that if you look in the main
panel at the wires feeding the subpanel, you'll find that when the subpanel
was installed, the black and red wires feeding it were connected to two
separate single-pole breakers (instead of to one double-pole breaker), and
those two breakers are on the same leg of the service.


That's fine -- just wasn't necessary for *this* application. But planning for
the future is always good. :-)

Troy writes:
ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?

Voltage is a potential difference. The difference between the two
current carrying conductors measures 240v. The difference between
a current carrying conductor and the grounded (aka neutral) conductor
is 120v. This being AC, rather than DC, the concept of a "return path"
doesn't really apply, per se. Note that the grounded conductor is
derived from a center-tap on the distribution transformer.


scott

Troy said:

ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?

You don't need a neutral to utilize the 220, in fact doing so negates
it from _being_ 220v. This is 180 degree out of phase AC, not DC.
All you need is a voltage potential and somewhere for it to travel,
for current to flow. This is provided by the two 120v out-of-phase
legs of your typical residential service. Hopefully you do not become
part of the conduction path, and is the primary reason that most
woodworking equipment requires a ground. It is not designed to be a
current carrying conductor.

Great confusion exists among novices as concerns Grounds and Neutrals,
especially when it involves outbuildings. Protection against
electrocution and lightning are two of the main reasons that the
current grounding guidelines/codes exist.

The ground on most 220vac equipment is for safety grounding only.
It is a ground, not a neutral, although they do eventually connect
together in your main panel, but never in an in-house subpanel.

Older stoves and cloths dryers sometimes used a common ground/neutral
to provide 120v for lamps and timer motors, but the new code and all
new appliances require a 4 conductor plug and wiring. Two hots, a
neutral, and a ground. It's a safety thing...

Get a copy of the NEC if you want to read up on how to wire things
safely, and to code. Otherwise, please, call an electrician.
Mistakes can be deadly and cause great property loss.

FWIW

DGG said:

Older stoves and cloths dryers sometimes used a common ground/neutral
to provide 120v for lamps and timer motors, but the new code and all
new appliances require a 4 conductor plug and wiring. Two hots, a
neutral, and a ground. It's a safety thing...

More precisely, should have read:

...all new 220v appliances that need the use of 120vac for
lamps/motors/etc. require a 4 conductor plug and wiring...

FWIW

In article , Troy wrote:
ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?

There isn't a "return path" per se in a 240V circuit. In a 120V circuit, the
hot is at a potential of 120V with respect to ground and neutral. In a 240V
circuit, the potential between the two hots is 240V; each is at a potential of
120V with respect to ground and neutral.

240v comes in and in the main service panel I know the nuetral and
ground are bonded.... never have understood that one.

That's to ensure that the neutral is at true earth ground potential.

then each leg of
the 240v is one side of the bus bar array in the service panel.
So what am I missing? I'm asking in all seriousness. I "added" a 220
outlet for my wife one day so she could have an electric stove and I
popped the breaker immeaditly when I fired it up because of the nuetral
being tied to ground.

That's not why you popped the breaker. Not having seen what you did, I can't
say why you *did* pop the breaker, but I can say with certainty that tying
neutral to ground didn't trip the breaker, in and of itself. Unless it was a
GFCI breaker.

So I shrugged said I don't get why its doing
that, read the directions with the receptacle and removed the nuetral.
All was well.

Means you had it connected to a hot lead somewhere...

I look at my dryer cord and its got 3 wires. I know the
top angled two are "hot" 120vac each and the other is the ground.
I realize that we can take a +12vdc and a -12vdc circuit and using only
2 wires get +24vdc across them and then have to have a chassis ground.

Yep, it's basically the same concept.

Man its been a long time since I studied electronics!

Residential electrical supply isn't quite the same animal. There are a number
of books available at any decent library or bookstore, or at most home
centers, if you want to learn more.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Troy wrote in :

uh? just the red & black? Where's the nuetral connected? You gotta
have a return circuit.
if you've got 10/3 then you've to red, black, white, ground right?
Am I missing something here or just don't know what I'm talking about.

Troy


Troy,

There are two 110 volt circuits in most CB boxes. Each is independent. They
also happen to be 180 degrees out of phase with one another. The upshot is
that while each is 120 volt with respect to ground, they are 220 volts with
respect to each other. The neutral is there for a variety of reasons but not
necessary for operation at 220vac. Ever wonder how your electric clothes
dryer works? The main coils are wired for 220 but the light bulb and other
parts like the timer use one side and the neutral.

Thanks!

With the groups help I was able to figure out what I was doing wrong.

As suggested I tested the main lugs in the subpanel I got 220v, but did
not get 220v when I tested the outlet accross both hots.

Turns out the the sub-panel installed only has two positions that will
give you 220v. I didn't connect the breaker to either one of these. I
removed the breaker, and re-connected it to the correct lugs and got
220v accross both hots. The heater now works! The inside of the panel
door has a diagram that shows which lugs are 120v and which are 220v.

Thanks for all your help!

SNIP
The main coils are wired for 220 but the light bulb and other
parts like the timer use one side and the neutral.


Wait, I thought we just got through learning there IS no neutral in a
240 circuit?? I didn't realize that they were out of phase with each other.

Troy

its been forever since I read any of the electrical code stuff and
OBVIOUSLY don't use it very often hardly. I'll be sure to ask any
questions before I mess with anything other then 120. At least I know
what I'm doing with that.

Troy

DGG wrote:
Troy said:


ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?


You don't need a neutral to utilize the 220, in fact doing so negates
it from _being_ 220v. This is 180 degree out of phase AC, not DC.
All you need is a voltage potential and somewhere for it to travel,
for current to flow. This is provided by the two 120v out-of-phase
legs of your typical residential service. Hopefully you do not become
part of the conduction path, and is the primary reason that most
woodworking equipment requires a ground. It is not designed to be a
current carrying conductor.

Great confusion exists among novices as concerns Grounds and Neutrals,
especially when it involves outbuildings. Protection against
electrocution and lightning are two of the main reasons that the
current grounding guidelines/codes exist.

The ground on most 220vac equipment is for safety grounding only.
It is a ground, not a neutral, although they do eventually connect
together in your main panel, but never in an in-house subpanel.

Older stoves and cloths dryers sometimes used a common ground/neutral
to provide 120v for lamps and timer motors, but the new code and all
new appliances require a 4 conductor plug and wiring. Two hots, a
neutral, and a ground. It's a safety thing...

Get a copy of the NEC if you want to read up on how to wire things
safely, and to code. Otherwise, please, call an electrician.
Mistakes can be deadly and cause great property loss.

FWIW

OK! now this makes sense.. I can center-tapping transformers sometimes
in multiple places as a youngster to get different voltages for power
supply's and ham radio circuits.

Troy

Scott Lurndal wrote:
Troy writes:

ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?


Voltage is a potential difference. The difference between the two
current carrying conductors measures 240v. The difference between
a current carrying conductor and the grounded (aka neutral) conductor
is 120v. This being AC, rather than DC, the concept of a "return path"
doesn't really apply, per se. Note that the grounded conductor is
derived from a center-tap on the distribution transformer.


scott

"Troy" wrote in message
...
SNIP
The main coils are wired for 220 but the light bulb and other
parts like the timer use one side and the neutral.


Wait, I thought we just got through learning there IS no neutral in a
240 circuit?? I didn't realize that they were out of phase with each
other.


No - the discussion was that for a 220V circuit, no neutral is needed.
However - when looking to also utilized 120V within a device that is hooked
up to a 220v circuit, then a neutral must be provided. The example given
was a clothes dryer. The dryer coils run on 220 and your clothes would dry
just fine with no neutral. However, the timer, any lights that may come on
when you open the door, etc. run on 110V. Therefore, you have to supply a
neutral so that those 110V devices can operate off of one leg of the 220V,
and neutral.

--

-Mike-

"Troy" wrote in message
...
SNIP
The main coils are wired for 220 but the light bulb and other parts like
the timer use one side and the neutral.


Wait, I thought we just got through learning there IS no neutral in a 240
circuit?? I didn't realize that they were out of phase with each other.

There is no neutral in a 240 volt circuit. Going from either leg of a 240
volt circuit to neutral gives you a 120 volt circuit.


Some appliances require both 120 and 240--they need a three-wire circuit
(two hots and a neutral) plus ground.

In article ,
says...

"Troy" wrote in message
...
SNIP
The main coils are wired for 220 but the light bulb and other parts like
the timer use one side and the neutral.


Wait, I thought we just got through learning there IS no neutral in a 240
circuit?? I didn't realize that they were out of phase with each other.

There is no neutral in a 240 volt circuit. Going from either leg of a 240
volt circuit to neutral gives you a 120 volt circuit.


Some appliances require both 120 and 240--they need a three-wire circuit
(two hots and a neutral) plus ground.



I've followed this thread and read some good questions and posts.
However, something of a trivial nature I guess, is the reference by some
to 110/220 VAC and others to 120/240 VAC. I grew up nearly always
hearing 110/220 until I worked several summers in college for an
electrical contractor. There, I found it was almost always really
120/240. Throughout my career, managing projects involving building
computer facilities and working around electricity, I've found the same
thing -- 120/240. I'm curious where the 110/220 terms/measurements came
from. Was that, at one time, the norm.

Tex

In article .net, Tex
wrote:

I'm curious where the 110/220 terms/measurements came
from. Was that, at one time, the norm.

Yes. It's gradually increased over time. 110, 115, 117, 120 -- some appliances
are marked 125 now.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

"R. Pierce Butler" writes:
Troy wrote in :

uh? just the red & black? Where's the nuetral connected? You gotta
have a return circuit.
if you've got 10/3 then you've to red, black, white, ground right?
Am I missing something here or just don't know what I'm talking about.

Troy


Troy,

There are two 110 volt circuits in most CB boxes. Each is independent. They
also happen to be 180 degrees out of phase with one another.

Actually, the 240 in 99% of US residential settings is single-phase,
using a center-tap to derive 120v. HV Distribution circuits are three
phase, with the phases 120 degrees apart. One of those phases feeds
the distribution transformer serving your residence, wherein there is
a center-tap which provides the neutral to the service entrance.

scott

It's AC, think about it. If you "know electronics" it should become obvious.

"Troy" wrote in message
...
ok, I know electronics, but am NOT an electrician. But I don't quite
get why we don't need a nuetral? Where's the return path?