Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit that would indicate the presence of voltage.
For instance I carry a little "pen" shaped device in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

On Dec 17, 10:59*am, klem kedidelhopper
wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit *that would indicate the presence of voltage.
For instance I carry a *little "pen" shaped device *in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

Neil S.

On Dec 17, 10:59*am, klem kedidelhopper
wrote:

For instance I carry a *little "pen" shaped device *in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Sure. You're describing a capacitive AC voltage sensor. Ground the end
of the tick tracer that you would normally hold. You have to rig a
mount that places the probe tip in proximity to the cable drop, and
couples the barrel to ground. But you only need to mount it when you
have a power outage, correct?

klem kedidelhopper wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

I have good luck with a battery operated AM radio. There is so much electical
noise where I live that AM stations are covered by it. When the power goes
out to the neighborhood it becomes clear.

I just turn on the radio and wait for the noise to come back and be stable.

Geoff.

--
Geoffrey S. Mendelson, N3OWJ/4X1GM
My high blood pressure medicine reduces my midichlorian count. :-(

On Dec 17, 3:04*pm, "Geoffrey S. Mendelson"
wrote:
klem kedidelhopper wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

I have good luck with a battery operated AM radio. There is so much electical
noise where I live that AM stations are covered by it. When the power goes
out to the neighborhood it becomes clear.

I just turn on the radio and wait for the noise to come back and be stable.

Geoff.

--
Geoffrey S. Mendelson, *N3OWJ/4X1GM
My high blood pressure medicine reduces my midichlorian count. :-(

I really like the NE2 capacitive probe idea. I've actually seen this
work around flyback transformers and fluorescent lamps but never
thought of trying it in this application. I'm going to experiment.
When you mentioned "neutral" Neil, connecting to ground on the service
entrance should work as well shouldn't it? And to answer Spamtrap's
question I would just as soon leave the probe in place all the time.
NE2's are cheap and the breaker box is on the other side of the room.
(You haven't seen my basement).
The AM radio scheme sounds like an interesting possibility too
however with all the CFL's, dimmers, switch mode power supplies, etc
in use today I don't now how "Quiet " my house would be even without
the utility.
I'm assuming that you may live in an apartment building Geoffrey with
many close by sources of noise. Our nearest neighbor is about 750 feet
from us so I don't think their noise contribution would be very
influential.
I am going to listen to this noise though at several different
frequencies next time power goes out and then compare it to the noise
when power is restored. I'm going to try the capacitive approach first
and I'll let everyone know how it works. Thanks, Lenny

klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

On Dec 17, 1:40*pm, Winston wrote:
klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. *They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. *The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

Winston, one of the main concerns that Lenny rightly had was
connecting to the entrance wires AHEAD of the main breakers. Your
average modern branch breaker is rated for 20,000A interrupting and
the main breaker for probably 50,000A. One cannot safely stick a 1/4A
3AG pigtail fuse off the mains to ptotect against a fault in your
'night lights'!

Some years ago I assisted in wiring a friends new house and for the
electric heat in the crawl space, we installed a neon indicator in a
box in the utility/laundry room to show when the crawl space heaters
were powered. I ordered a neon panel indicator rated for 240V and
double checked it's markings along with the carton information to be
assured it was for 240V. It was connected across the 240V 30A supply
to those heaters and the breaker switched on. Ka-boom !! Fortunately
the breaker panel was not in that room since it was showered by shards
of the Bakelite box cover and fragments of the neon bulb and holder
plus there were nice black marks radiating on the wall around the box.
A replacement indicator [same type] worked fine for years.

Neil S.

On Dec 17, 5:12*pm, nesesu wrote:
On Dec 17, 1:40*pm, Winston wrote:



klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. *They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. *The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

Winston, one of the main concerns that Lenny rightly had was
connecting to the entrance wires AHEAD of the main breakers. Your
average modern branch breaker is rated for 20,000A interrupting and
the main breaker for probably 50,000A. One cannot safely stick a 1/4A
3AG pigtail fuse off the mains to ptotect against a fault in your
'night lights'!

Some years ago I assisted in wiring a friends new house and for the
electric heat in the crawl space, we installed a neon indicator in a
box in the utility/laundry room to show when the crawl space heaters
were powered. I ordered a neon panel indicator rated for 240V and
double checked it's markings along with the carton *information to be
assured it was for 240V. It was connected across the 240V 30A supply
to those heaters and the breaker switched on. Ka-boom !! Fortunately
the breaker panel was not in that room since it was showered by shards
of the Bakelite box cover and fragments of the neon bulb and holder
plus there were nice black marks radiating on the wall around the box.
A replacement indicator [same type] worked fine for years.

Neil S.

I do like the idea of monitoring each side of the 240 as you had
suggested Winston. I have gotten equipment in here in the past for
repair which had been severely damaged by a loss of the neutral, or
some other imbalance as you had mentioned. However I have to agree
with Neil about isolation. If there is a way to do this without
physically connecting to the utility ahead of all circuit protection I
would like to explore that option first. Lenny

nesesu wrote:
On Dec 17, 1:40 pm, wrote:
klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

Winston, one of the main concerns that Lenny rightly had was
connecting to the entrance wires AHEAD of the main breakers. Your
average modern branch breaker is rated for 20,000A interrupting and
the main breaker for probably 50,000A. One cannot safely stick a 1/4A
3AG pigtail fuse off the mains to ptotect against a fault in your
'night lights'!

I can see how it might be a difficulty WRT the NEC.
I imagine they forbid *any* kind of load 'north'
of the branch circuits.

But looked at from a sheer electrical engineering
standpoint, I don't understand why fuses off of
L1 and L2 should not be adequate protection for
these indicators, even connected right to the
input horn. Theoretically speaking, of course.

The power company uses inductive coupled sensors
far 'north' of the consumer's branch circuits.
Perhaps it is legal, moral and correct to use
inductive sensing in a residential power
situation as mentioned upthread?

http://www.selinc.com/FCI/FaultIndicatorsandSensors/

Some years ago I assisted in wiring a friends new house and for the
electric heat in the crawl space, we installed a neon indicator in a
box in the utility/laundry room to show when the crawl space heaters
were powered. I ordered a neon panel indicator rated for 240V and
double checked it's markings along with the carton information to be
assured it was for 240V. It was connected across the 240V 30A supply
to those heaters and the breaker switched on. Ka-boom !! Fortunately
the breaker panel was not in that room since it was showered by shards
of the Bakelite box cover and fragments of the neon bulb and holder
plus there were nice black marks radiating on the wall around the box.
A replacement indicator [same type] worked fine for years.

That is weird!

--Winston

On Dec 18, 1:20*am, Winston wrote:
nesesu wrote:
On Dec 17, 1:40 pm, *wrote:
klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. *They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. *The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

Winston, one of the main concerns that Lenny rightly had was
connecting to the entrance wires AHEAD of the main breakers. Your
average modern branch breaker is rated for 20,000A interrupting and
the main breaker for probably 50,000A. One cannot safely stick a 1/4A
3AG pigtail fuse off the mains to ptotect against a fault in your
'night lights'!

I can see how it might be a difficulty WRT the NEC.
I imagine they forbid *any* kind of load 'north'
of the branch circuits.

But looked at from a sheer electrical engineering
standpoint, I don't understand why fuses off of
L1 and L2 should not be adequate protection for
these indicators, even connected right to the
input horn. Theoretically speaking, of course.

The power company uses inductive coupled sensors
far 'north' of the consumer's branch circuits.
Perhaps it is legal, moral and correct to use
inductive sensing in a residential power
situation as mentioned upthread?

http://www.selinc.com/FCI/FaultIndicatorsandSensors/

Some years ago I assisted in wiring a friends new house and for the
electric heat in the crawl space, we installed a neon indicator in a
box in the utility/laundry room to show when the crawl space heaters
were powered. I ordered a neon panel indicator rated for 240V and
double checked it's markings along with the carton *information to be
assured it was for 240V. It was connected across the 240V 30A supply
to those heaters and the breaker switched on. Ka-boom !! Fortunately
the breaker panel was not in that room since it was showered by shards
of the Bakelite box cover and fragments of the neon bulb and holder
plus there were nice black marks radiating on the wall around the box.
A replacement indicator [same type] worked fine for years.

That is weird!

--Winston

Except for the fact that the fuses and lamps would have to be "moused"
into the panel before the main breaker in some sort of safe way, I
guess from a theoretical point of view it would seem like a workable
safe plan. However in looking at it from a strictly pragmatic point of
view I guess that I must consider the litigious society we all
unfortunately live in as well. There is always the possibility of an
insurance inspector seeing that modification on a disconnect after a
fire.

Even if the fire was caused by something totally unrelated to the
modification everyone knows that the last thing most insurance
companies will come across with is a check. And since this
modification, however technically feasible and safe would be a
violation of the NEC, subsequently a case could still be made for
noncompliance and therefore, no money. I hate to have to think this
way but I guess we all should. The inductive, or capacitive approach
would totally eliminate that factor from the equation.

I do have one question though Neil about the experiment that you
initially suggested. I can understand how wrapping the one foot length
of #22 wire around the piece of cable which simulates my entrance
cable would capacitively/inductively, or both couple the AC to the NE2
lamp, however in actual practice I won't be able to wrap just one
conductor of the entrance cable outside of the panel as they're both
together in a jacket. I would think if I were to wrap both, every time
I'd cross the pair, the second wrap would be out of phase with the
first and the net induction into my "probe" would be zero. I could get
into the panel and without making a direct electrical connection wrap
just one or both of the mains, (if I do an indicator for each phase),
and perhaps that's what you had in mind? Or am I looking at this
incorrectly? Lenny

On Dec 18, 5:08*am, klem kedidelhopper
wrote:
On Dec 18, 1:20*am, Winston wrote:





nesesu wrote:
On Dec 17, 1:40 pm, *wrote:
klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. *They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. *The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

Winston, one of the main concerns that Lenny rightly had was
connecting to the entrance wires AHEAD of the main breakers. Your
average modern branch breaker is rated for 20,000A interrupting and
the main breaker for probably 50,000A. One cannot safely stick a 1/4A
3AG pigtail fuse off the mains to ptotect against a fault in your
'night lights'!

I can see how it might be a difficulty WRT the NEC.
I imagine they forbid *any* kind of load 'north'
of the branch circuits.

But looked at from a sheer electrical engineering
standpoint, I don't understand why fuses off of
L1 and L2 should not be adequate protection for
these indicators, even connected right to the
input horn. Theoretically speaking, of course.

The power company uses inductive coupled sensors
far 'north' of the consumer's branch circuits.
Perhaps it is legal, moral and correct to use
inductive sensing in a residential power
situation as mentioned upthread?

http://www.selinc.com/FCI/FaultIndicatorsandSensors/

Some years ago I assisted in wiring a friends new house and for the
electric heat in the crawl space, we installed a neon indicator in a
box in the utility/laundry room to show when the crawl space heaters
were powered. I ordered a neon panel indicator rated for 240V and
double checked it's markings along with the carton *information to be
assured it was for 240V. It was connected across the 240V 30A supply
to those heaters and the breaker switched on. Ka-boom !! Fortunately
the breaker panel was not in that room since it was showered by shards
of the Bakelite box cover and fragments of the neon bulb and holder
plus there were nice black marks radiating on the wall around the box..
A replacement indicator [same type] worked fine for years.

That is weird!

--Winston

Except for the fact that the fuses and lamps would have to be "moused"
into the panel before the main breaker in some sort of safe way, I
guess from a theoretical point of view it would seem like a workable
safe plan. However in looking at it from a strictly pragmatic point of
view I guess that I must consider the litigious society we all
unfortunately live in as well. There is always the possibility of an
insurance inspector seeing that modification on a disconnect after a
fire.

Even if the fire was caused by something totally unrelated to the
modification everyone knows that the last thing most insurance
companies will come across with is a check. And since this
modification, however technically feasible and safe would be a
violation of the NEC, subsequently a case could still be made for
noncompliance and therefore, no money. I hate to have to think this
way but I guess we all should. The inductive, or capacitive approach
would totally eliminate that factor from the equation.

I do have one question though Neil about the experiment that you
initially suggested. I can understand how wrapping the one foot length
of #22 wire around the piece of cable which simulates my entrance
cable would capacitively/inductively, or both couple the AC to the NE2
lamp, however in actual practice I won't be able to wrap just one
conductor of the entrance cable outside of the panel as they're both
together in a jacket. I would think if I were to wrap both, every time
I'd cross the pair, the second wrap would be out of phase with the
first and the net induction into my "probe" would be zero. I could get
into the panel and without making a direct electrical connection wrap
just one or both of the mains, (if I do an indicator for each phase),
and perhaps that's what you had in mind? Or am I looking at this
incorrectly? Lenny- Hide quoted text -

- Show quoted text -

Lenny, my suggestion was to wrap the 'probe' wire around each 'line'
conductor of the incoming service cable which would have to be done
inside the entrance section of the breaker panel or disconnect switch
[depending on what sort of installation you have]. As you correctly
surmise, wrapping around the full cable will have no significant
sensing ability. However, if you have type SE cable coming in [at
least that is what it's called here in Canada, but is relatively
rarely used] you could probably use the circuit sensor probe on the
outside of the sheath since in the few examples I have seen, the
spiral wrap neutral conductor strands are not close together and I
suspect that there would be enough electostatic field at the sheath to
measure. The usual service cable around here [BC] is either type TECK
or in conduit, neither of which allows easy monitoring.

My description of the result of a faulty indicator was simply to show
that even properly installed equipment can potentially cause serious
problems under fault conditions.

Neil S.

On Dec 18, 11:34*am, nesesu wrote:
On Dec 18, 5:08*am, klem kedidelhopper
wrote:



On Dec 18, 1:20*am, Winston wrote:

nesesu wrote:
On Dec 17, 1:40 pm, *wrote:
klem kedidelhopper wrote:
Our area suffers from frequent blackouts,

(...)

In addition to the insights by other posters, if you
have standard U.S. 'split phase' service, please
consider an indicator for each half - phase.

Consider using two 4 W 'night lights'. *They won't
be fooled by electrical noise on the line, as the
neon lights might.

So L1 to neutral gets a lamp and L2 to neutral gets
another lamp. *The reason I mention this is that
the last three 'brownouts' in my area were characterized
by the total loss of L1 and very low voltage from
L2 to neutral.

--Winston

Winston, one of the main concerns that Lenny rightly had was
connecting to the entrance wires AHEAD of the main breakers. Your
average modern branch breaker is rated for 20,000A interrupting and
the main breaker for probably 50,000A. One cannot safely stick a 1/4A
3AG pigtail fuse off the mains to ptotect against a fault in your
'night lights'!

I can see how it might be a difficulty WRT the NEC.
I imagine they forbid *any* kind of load 'north'
of the branch circuits.

But looked at from a sheer electrical engineering
standpoint, I don't understand why fuses off of
L1 and L2 should not be adequate protection for
these indicators, even connected right to the
input horn. Theoretically speaking, of course.

The power company uses inductive coupled sensors
far 'north' of the consumer's branch circuits.
Perhaps it is legal, moral and correct to use
inductive sensing in a residential power
situation as mentioned upthread?

http://www.selinc.com/FCI/FaultIndicatorsandSensors/

Some years ago I assisted in wiring a friends new house and for the
electric heat in the crawl space, we installed a neon indicator in a
box in the utility/laundry room to show when the crawl space heaters
were powered. I ordered a neon panel indicator rated for 240V and
double checked it's markings along with the carton *information to be
assured it was for 240V. It was connected across the 240V 30A supply
to those heaters and the breaker switched on. Ka-boom !! Fortunately
the breaker panel was not in that room since it was showered by shards
of the Bakelite box cover and fragments of the neon bulb and holder
plus there were nice black marks radiating on the wall around the box.
A replacement indicator [same type] worked fine for years.

That is weird!

--Winston

Except for the fact that the fuses and lamps would have to be "moused"
into the panel before the main breaker in some sort of safe way, I
guess from a theoretical point of view it would seem like a workable
safe plan. However in looking at it from a strictly pragmatic point of
view I guess that I must consider the litigious society we all
unfortunately live in as well. There is always the possibility of an
insurance inspector seeing that modification on a disconnect after a
fire.

Even if the fire was caused by something totally unrelated to the
modification everyone knows that the last thing most insurance
companies will come across with is a check. And since this
modification, however technically feasible and safe would be a
violation of the NEC, subsequently a case could still be made for
noncompliance and therefore, no money. I hate to have to think this
way but I guess we all should. The inductive, or capacitive approach
would totally eliminate that factor from the equation.

I do have one question though Neil about the experiment that you
initially suggested. I can understand how wrapping the one foot length
of #22 wire around the piece of cable which simulates my entrance
cable would capacitively/inductively, or both couple the AC to the NE2
lamp, however in actual practice I won't be able to wrap just one
conductor of the entrance cable outside of the panel as they're both
together in a jacket. I would think if I were to wrap both, every time
I'd cross the pair, the second wrap would be out of phase with the
first and the net induction into my "probe" would be zero. I could get
into the panel and without making a direct electrical connection wrap
just one or both of the mains, (if I do an indicator for each phase),
and perhaps that's what you had in mind? Or am I looking at this
incorrectly? Lenny- Hide quoted text -

- Show quoted text -

Lenny, my suggestion was to wrap the 'probe' wire around each 'line'
conductor of the incoming service cable which would have to be done
inside the entrance section of the breaker panel or disconnect switch
[depending on what sort of installation you have]. As you correctly
surmise, wrapping around the full cable will have no significant
sensing ability. However, if you have type SE cable coming in [at
least that is what it's called here in Canada, but is relatively
rarely used] you could probably use the circuit sensor probe on the
outside of the sheath since in the few examples I have seen, the
spiral wrap neutral conductor strands are not close together and I
suspect that there would be enough electostatic field at the sheath to
measure. The usual service cable around here [BC] is either type TECK
or in conduit, neither of which allows easy monitoring.

My description of the result of a faulty indicator was simply to show
that even properly installed equipment can potentially cause serious
problems under fault conditions.

Neil S.
Neil
When you say "you can probably use the circuit sensor probe on the
outside of the sheath", what if I made the probe wire somewhat longer
and just merely "laid" it up against one of the entrance conductors
for a distance outside of the panel? I could tape it in place. (If
this worked I'd use one on each phase). If I'm understanding this
correctly when you "wrap" the probe wire around the conductor that
would appear to be induction, (transformer of sorts), and if you were
to just "lay" the probe wire against the cable then that would seem
like capacitive coupling? I don't know what kind of field we're
dealing with here however I would suspect that the magnitude of both
induction and capacitive coupling would be directly proportional to
the size, or rather the length of the probe, right? Lenny

I almost hate to say anything because there are so many variables.
First of all in most places the insurance company can't get out of
paying because of non-compliance unless that is the cause of the loss.
In this case if the non-compliance still exists it was not the cause
of the loss and if it is, it would be gone. The capacitive method is a
nice idea but I think it would be too easily fooled by circumstances.

First of all take the case of if the power ison, here in the city
there is always 60Hz SOMEWHERE and could be picked up capacitively
even if power is not restored. If you connect a high impedance DVM or
VTVM to the power lines when it's out it will likely read some
voltage. That's why alot of electricians use what's called a Wiggy.
This type of meter presents enough of a load to make sure that when it
says a circuit is live, it is really live. It's a similar comcept to
using a battery tester instead of a meter, to find out if there is any
current behind it.

At 60 Hz of course you can't just put the bulb near and have it glow,
so you wrap the wire(s). Getting enough area for the plates of this
"capacitor" is the key of course. If you have Romex type entrance
cable you would have to tape it along the sides, if it's in conduit
you need to get inside the box.

If you are turning off the main breaker and backfeeding the panel,
that's not quite the way to do it. There are setups available for this
purpose at electrical supply places. First of all the first thing the
mains must hit is a main breaker or disconnect. Unfortunately you need
to be before this. Since this pain in the ass exists why not just get
another box that will hold a relay to switch it automatically ? It's
probably about a hundred bucks in components tops, and that should
include the enclosure and whatever wire needed. A relay simply
switches the source. It pulls the relay with line voltage, when it is
gone it switches over. With some minor enhancements you can make it
shut off the generator as soon as power is restored, and if you want
to get fancy and the generator has electric start the whole thing can
be automated.

There are products available that do just that, but you CAN DIY this
if you mind the NEC and local codes. If you DIY, mount a dorrbell Xfmr
in a box right on the side of the main panel. Hold a relay open with
it for the ignition of whatever cutoff the generator has (can be a
problem if it's deisel). To have it autostart the main problem is
sensing when the engine is actually running to disengage the starter
motor. There are several methods of doing this, and some generators
are setup for it already. It all depends on exactly what you have.

However, if you look for example at Grainger, the proper enclosures
are available. What makes it legal is the doorbell Xfmr, which must be
installed a certain way. Then whatever you do with the 24 volts
doesn't mtter because it is class two. Remember class one and two
wiring must be separate, and even with class two you can't do just
anything you want.

Tell ya what, since it's a lazy Sunday afternoon I'll have a look
around, I bet what you need is available, and for less than a hundred
bucks.

J

"If I'm understanding this
correctly when you "wrap" the probe wire around the conductor that
would appear to be induction, (transformer of sorts), "

That is correct if you provide a return path at the other end of the
wire. Doing that will make it sense current inductively. If you leave
it open it wil detect the voltage capacitively.

J

On Dec 17, 1:50*pm, nesesu wrote:
On Dec 17, 10:59*am, klem kedidelhopper
wrote:





Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit *that would indicate the presence of voltage.
For instance I carry a *little "pen" shaped device *in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

Neil S.- Hide quoted text -

- Show quoted text -

Fantastic idea!!!

On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper
wrote:

Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

The neon lamp method works. You'll need one for each phase.

However, I smell a different problem. I couldn't see why you would
need to monitor the voltage before the main breaker. If you had a
proper transfer switch, it wouldn't be necessary:
http://www2.northerntool.com/generators/transfer-switches-4.htm
If you're powering some appliances with an extension cord, you can
tell if the power has returned when the house lights come back on.

My guess(tm) is that you're opening the main breaker when the power
dies, and back feeding a wall outlet with a suicide cord (a power plug
on each end of the cable). If you're really clever, you'll backfeed
both phases with a 220VAC suicide cord.

The 220VAC version will work, but the single phase suicide cord has a
problem. Under normal conditions, the current through the neutral
wire is nearly zero. That's because the 180 degree phase difference
between each phase cancels the current in the neutral wire. However,
with only one phase powered, you're likely to see the full current
through the neutral. If you're creative and parallel both phases,
then the neutral current is even higher. Code compliant wiring can
survive this, but I've seen a few blown neutrals. That's when the
neutral wiring was rotten, and nobody noticed until the full current
was applied.

Another problem is that when you back feed a single wall outlet with a
suicide cord, you're going to be limited by the current limit of the
connected circuit breaker. In the US, that's about 15A. That should
be sufficient for most loads, but I suggest to disconnect the high
current loads to prevent blowing the breaker.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Dec 18, 11:18*pm, Jeff Liebermann wrote:
On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper

wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

The neon lamp method works. *You'll need one for each phase.

However, I smell a different problem. *I couldn't see why you would
need to monitor the voltage before the main breaker. *If you had a
proper transfer switch, it wouldn't be necessary:
http://www2.northerntool.com/generators/transfer-switches-4.htm
If you're powering some appliances with an extension cord, you can
tell if the power has returned when the house lights come back on.

My guess(tm) is that you're opening the main breaker when the power
dies, and back feeding a wall outlet with a suicide cord (a power plug
on each end of the cable). *If you're really clever, you'll backfeed
both phases with a 220VAC suicide cord.

The 220VAC version will work, but the single phase suicide cord has a
problem. *Under normal conditions, the current through the neutral
wire is nearly zero. *That's because the 180 degree phase difference
between each phase cancels the current in the neutral wire. *However,
with only one phase powered, you're likely to see the full current
through the neutral. *If you're creative and parallel both phases,
then the neutral current is even higher. *Code compliant wiring can
survive this, but I've seen a few blown neutrals. *That's when the
neutral wiring was rotten, and nobody noticed until the full current
was applied.

Another problem is that when you back feed a single wall outlet with a
suicide cord, you're going to be limited by the current limit of the
connected circuit breaker. *In the US, that's about 15A. *That should
be sufficient for most loads, but I suggest to disconnect the high
current loads to prevent blowing the breaker.

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-2558

I think that what you may be talking about Jeff is an "automatic"
transfer operation. This sounds like a system that will automatically
start the generator on sensing a loss of power, and then activate a
huge double pole contactor. Then when power is restored the generator
is stopped, and the contactor switches state. This is a whole house
system and you're correct in that you would not need to monitor the
utility because the generator system would do it for you. However if
you look at the first example of a transfer switch on the page you
included with your post you'll notice that the example is a manual
switch which controls six circuits. To utilize this switch you pull
six loads out of your panel and wire them through this switch. The
generator is manually operated and essentially the utility mains is on
one side of a double pole switch, (if you will), the generator is on
the other side, and the load, (house) is in the center. In any case
and regardless of what system you use, there can't be any connection
between your generator and the transformer on the pole. Therefore, and
please correct me if I'm wrong but it would seem that with any manual
system, whether you use one of these manual switches or you back feed
a 240 volt circuit and manually kill the main, you would have no way
of knowing when the utility is back in service. Lenny

On Dec 19, 6:08*am, klem kedidelhopper
wrote:
On Dec 18, 11:18*pm, Jeff Liebermann wrote:









On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper

wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

The neon lamp method works. *You'll need one for each phase.

However, I smell a different problem. *I couldn't see why you would
need to monitor the voltage before the main breaker. *If you had a
proper transfer switch, it wouldn't be necessary:
http://www2.northerntool.com/generators/transfer-switches-4.htm
If you're powering some appliances with an extension cord, you can
tell if the power has returned when the house lights come back on.

My guess(tm) is that you're opening the main breaker when the power
dies, and back feeding a wall outlet with a suicide cord (a power plug
on each end of the cable). *If you're really clever, you'll backfeed
both phases with a 220VAC suicide cord.

The 220VAC version will work, but the single phase suicide cord has a
problem. *Under normal conditions, the current through the neutral
wire is nearly zero. *That's because the 180 degree phase difference
between each phase cancels the current in the neutral wire. *However,
with only one phase powered, you're likely to see the full current
through the neutral. *If you're creative and parallel both phases,
then the neutral current is even higher. *Code compliant wiring can
survive this, but I've seen a few blown neutrals. *That's when the
neutral wiring was rotten, and nobody noticed until the full current
was applied.

Another problem is that when you back feed a single wall outlet with a
suicide cord, you're going to be limited by the current limit of the
connected circuit breaker. *In the US, that's about 15A. *That should
be sufficient for most loads, but I suggest to disconnect the high
current loads to prevent blowing the breaker.

I think that what you may be talking about Jeff is an "automatic"
transfer operation. This sounds like a system that will automatically
start the generator on sensing a loss of power, and then activate a
huge double pole contactor. Then when power is restored the generator
is stopped, and the contactor switches state. This is a whole house
system and you're correct in that you would not need to monitor the
utility because the generator system would do it for you. However if
you look at the first example of a transfer switch on the page you
included with your post you'll notice that the example is a manual
switch which controls six circuits. To utilize this switch you pull
six loads out of your panel and wire them through this switch. The
generator is manually operated and essentially the utility mains is on
one side of a double pole switch, (if you will), the generator is on
the other side, and the load, (house) is in the center. In any case
and regardless of what system you use, there can't be any connection
between your generator and the transformer on the pole. Therefore, and
please correct me if I'm wrong but *it would seem that with any manual
system, whether you use one of these manual switches or you back feed
a 240 volt circuit and manually kill the main, you would have no way
of knowing when the utility is back in service. Lenny

I suggest that Klem adopt this philosophy of life, instead of being
Nick Negative:

"As you go through life, make this your goal: Keep your eye on the
doughnut and not on the hole."

The manual transfer switches connect only certain house circuits to a
portable generator -- presumably those powering appliances that the
homeowner deems to be critical. The rest of the household circuits
will be unenergized until the mains power is back on. So the owner
will know to shut the generator off when all the lights and radios,
etc. come on.

On Dec 19, 9:41*am, spamtrap1888 wrote:
On Dec 19, 6:08*am, klem kedidelhopper
wrote:



On Dec 18, 11:18*pm, Jeff Liebermann wrote:

On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper

wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

The neon lamp method works. *You'll need one for each phase.

However, I smell a different problem. *I couldn't see why you would
need to monitor the voltage before the main breaker. *If you had a
proper transfer switch, it wouldn't be necessary:
http://www2.northerntool.com/generators/transfer-switches-4.htm
If you're powering some appliances with an extension cord, you can
tell if the power has returned when the house lights come back on.

My guess(tm) is that you're opening the main breaker when the power
dies, and back feeding a wall outlet with a suicide cord (a power plug
on each end of the cable). *If you're really clever, you'll backfeed
both phases with a 220VAC suicide cord.

The 220VAC version will work, but the single phase suicide cord has a
problem. *Under normal conditions, the current through the neutral
wire is nearly zero. *That's because the 180 degree phase difference
between each phase cancels the current in the neutral wire. *However,
with only one phase powered, you're likely to see the full current
through the neutral. *If you're creative and parallel both phases,
then the neutral current is even higher. *Code compliant wiring can
survive this, but I've seen a few blown neutrals. *That's when the
neutral wiring was rotten, and nobody noticed until the full current
was applied.

Another problem is that when you back feed a single wall outlet with a
suicide cord, you're going to be limited by the current limit of the
connected circuit breaker. *In the US, that's about 15A. *That should
be sufficient for most loads, but I suggest to disconnect the high
current loads to prevent blowing the breaker.
I think that what you may be talking about Jeff is an "automatic"
transfer operation. This sounds like a system that will automatically
start the generator on sensing a loss of power, and then activate a
huge double pole contactor. Then when power is restored the generator
is stopped, and the contactor switches state. This is a whole house
system and you're correct in that you would not need to monitor the
utility because the generator system would do it for you. However if
you look at the first example of a transfer switch on the page you
included with your post you'll notice that the example is a manual
switch which controls six circuits. To utilize this switch you pull
six loads out of your panel and wire them through this switch. The
generator is manually operated and essentially the utility mains is on
one side of a double pole switch, (if you will), the generator is on
the other side, and the load, (house) is in the center. In any case
and regardless of what system you use, there can't be any connection
between your generator and the transformer on the pole. Therefore, and
please correct me if I'm wrong but *it would seem that with any manual
system, whether you use one of these manual switches or you back feed
a 240 volt circuit and manually kill the main, you would have no way
of knowing when the utility is back in service. Lenny

I suggest that Klem adopt this philosophy of life, instead of being
Nick Negative:

"As you go through life, make this your goal: Keep your eye on the
doughnut and not on the hole."

The manual transfer switches connect only certain house circuits to a
portable generator -- presumably those powering appliances that the
homeowner deems to be critical. The rest of the household circuits
will be unenergized until the mains power is back on. So the owner
will know to shut the generator off when all the lights and radios,
etc. come on.

Thank you for correcting me on that point. But in what way was I being
negative? Doughnuts are no good for you. Lenny

On Dec 19, 7:03*am, klem kedidelhopper
wrote:
On Dec 19, 9:41*am, spamtrap1888 wrote:









On Dec 19, 6:08*am, klem kedidelhopper
wrote:

On Dec 18, 11:18*pm, Jeff Liebermann wrote:

On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper

wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

The neon lamp method works. *You'll need one for each phase.

However, I smell a different problem. *I couldn't see why you would
need to monitor the voltage before the main breaker. *If you had a
proper transfer switch, it wouldn't be necessary:
http://www2.northerntool.com/generators/transfer-switches-4.htm
If you're powering some appliances with an extension cord, you can
tell if the power has returned when the house lights come back on.

My guess(tm) is that you're opening the main breaker when the power
dies, and back feeding a wall outlet with a suicide cord (a power plug
on each end of the cable). *If you're really clever, you'll backfeed
both phases with a 220VAC suicide cord.

The 220VAC version will work, but the single phase suicide cord has a
problem. *Under normal conditions, the current through the neutral
wire is nearly zero. *That's because the 180 degree phase difference
between each phase cancels the current in the neutral wire. *However,
with only one phase powered, you're likely to see the full current
through the neutral. *If you're creative and parallel both phases,
then the neutral current is even higher. *Code compliant wiring can
survive this, but I've seen a few blown neutrals. *That's when the
neutral wiring was rotten, and nobody noticed until the full current
was applied.

Another problem is that when you back feed a single wall outlet with a
suicide cord, you're going to be limited by the current limit of the
connected circuit breaker. *In the US, that's about 15A. *That should
be sufficient for most loads, but I suggest to disconnect the high
current loads to prevent blowing the breaker.
I think that what you may be talking about Jeff is an "automatic"
transfer operation. This sounds like a system that will automatically
start the generator on sensing a loss of power, and then activate a
huge double pole contactor. Then when power is restored the generator
is stopped, and the contactor switches state. This is a whole house
system and you're correct in that you would not need to monitor the
utility because the generator system would do it for you. However if
you look at the first example of a transfer switch on the page you
included with your post you'll notice that the example is a manual
switch which controls six circuits. To utilize this switch you pull
six loads out of your panel and wire them through this switch. The
generator is manually operated and essentially the utility mains is on
one side of a double pole switch, (if you will), the generator is on
the other side, and the load, (house) is in the center. In any case
and regardless of what system you use, there can't be any connection
between your generator and the transformer on the pole. Therefore, and
please correct me if I'm wrong but *it would seem that with any manual
system, whether you use one of these manual switches or you back feed
a 240 volt circuit and manually kill the main, you would have no way
of knowing when the utility is back in service. Lenny

I suggest that Klem adopt this philosophy of life, instead of being
Nick Negative:

"As you go through life, make this your goal: Keep your eye on the
doughnut and not on the hole."

The manual transfer switches connect only certain house circuits to a
portable generator -- presumably those powering appliances that the
homeowner deems to be critical. The rest of the household circuits
will be unenergized until the mains power is back on. So the owner
will know to shut the generator off when all the lights and radios,
etc. come on.

Thank you for correcting me on that point. But in what way was I being
negative? Doughnuts are no good for you. Lenny

Jeff gave you your answer, but you rejected it instead of trying to
understand how it met your needs.

On Dec 18, 3:22*pm, Jeff Urban wrote:
"If I'm understanding this
correctly when you "wrap" the probe wire around the conductor that
would appear to be induction, (transformer of sorts), "

That is correct if you provide a return path at the other end of the
wire. Doing that will make it sense current inductively. If you leave
it open it wil detect the voltage capacitively.

J

But the "return path" coil will then detect current, not voltage. I
think the capacitive idea is better, but you might need a bit of load
on it to avoid false detection of noise on the line.
Cheers.
Roger

On Mon, 19 Dec 2011 06:08:43 -0800 (PST), klem kedidelhopper
wrote:

I think that what you may be talking about Jeff is an "automatic"
transfer operation. This sounds like a system that will automatically
start the generator on sensing a loss of power, and then activate a
huge double pole contactor.

Yes, I mentioned that in one sentence. That's the correct way to wire
an emergency generator to a house. However, I continued beyond that
sentence and attempted to reverse engineer what you're doing with the
generator, and guessed that you are back feeding the wall outlet with
a suicide cord. If this is correct, there are safety issues involved,
some of which I detailed. You might want to re-read what I scribbled.
Therefore, and
please correct me if I'm wrong but it would seem that with any manual
system, whether you use one of these manual switches or you back feed
a 240 volt circuit and manually kill the main, you would have no way
of knowing when the utility is back in service. Lenny

Again, please re-read my previous 2nd paragraph. If you are powering
a few appliances from the generator via an extension cord, and NOT
backfeeding the wall outlets, then you'll know when the power is back
on when the house lights return to normal. The reason you probably
can't tell that the power is back on is that you have switched the
main breaker to off. You'll need a neon lamp capacitive sensor.

Flipping the main breaker on, while the generator is running, is a
great way of blowing up some generators. Flipping the breaker on,
while the generator is running, while the power company is working on
the lines, is a hazard to the lineman. However, they protect
themselves by shorting or grounding the lines, which will usually blow
the output breakers on your generator.

The bottom line is that you really should spend the money on a proper
transfer switch. It does NOT need to be automatic. Manual transfer
switches are much cheaper and good enough. If you have an autostart
generator, you will need an automatic transfer switch. If not, use a
manual switch:
http://www2.northerntool.com/generators/transfer-switches-4.htm
www.amazon.com/s?ie=UTF81&keywords=manual transfer switch
http://www.reliancecontrols.com/Documents/S1204TE.pdf

Some transfer switches are *NOT* intended to run the entire house.
They have their own breakers and their own loads off a sub-panel.
See Fig 3 wiring diagram at:
http://www.renovation-headquarters.com/generator-transfer-switch.htm
When the power returns, the lights and devices that are NOT powered by
the transfer box, come back on. Meanwhile the generator is still
running the rest of the outlets. Flip the switch, and these loads are
now on utility power. Then, you can turn off the generator.

Other transfer switches switch the entire breaker panel.
http://www.reliancecontrols.com/ProductDetail.aspx?TCA1006D
Since these are installed between the meter and the breaker box,
you'll know that power had returned when the meter starts moving.

Note: I have 3 generators, none of which work. Yet another project.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper
wrote:

Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit that would indicate the presence of voltage.
For instance I carry a little "pen" shaped device in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny
I can see four approaches, one of which which may meet your needs.

The 'Neon light with capacitove link' would certainly be inexpensive,
however I question if sufficient current would be generated to light a
neon bulb. It would be easy to test, and I might actually try it
sometime. If I can find my neon tester. It's probably with my tube
tester. (Shoot, it should be possible to calculate the area of
foil required!!)

I have a Christmas Tree Light Tester. It uses capacitive pickup to
sense the voltage differential to indicate if the wires are at close
to the same voltage (good light) or at different voltages (light bulb
burned out). LEDs light to indicate the status when the button is
pressed. Less than $10 at K-Mart, as I recall. With a little
'circuit bending' it could produce the results you desire.

You didn't indicate how much current and the number of circuits the
generator is supplying. One approach would be to add an expansion
circuit breaker panel next to the present panel, and power all
'emergency' circuits through the expansion panel. The lines from the
main panel would go through a circuit breaker in the main panel and
another in the expansion panel. Switchover would be handled by
opening the breaker accepting current from the main panel and closing
the one accepting current from the generator (someone mechanically
clever could build an interlock so both could not be closed at the
same time).

Of course, there are also the commercially available switches; I find
the price of them to be excessive, even the manual ones.

PlainBill

On Dec 18, 10:18*pm, Jeff Liebermann wrote:
On Sat, 17 Dec 2011 10:59:52 -0800 (PST), klem kedidelhopper

wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.

The neon lamp method works. *You'll need one for each phase.

However, I smell a different problem. *I couldn't see why you would
need to monitor the voltage before the main breaker. *If you had a
proper transfer switch, it wouldn't be necessary:
http://www2.northerntool.com/generators/transfer-switches-4.htm
If you're powering some appliances with an extension cord, you can
tell if thepowerhas returned when the house lights come back on.

My guess(tm) is that you're opening the main breaker when thepower
dies, and back feeding a wall outlet with a suicide cord (apowerplug
on each end of the cable). *If you're really clever, you'll backfeed
both phases with a 220VAC suicide cord.

The 220VAC version will work, but the single phase suicide cord has a
problem. *Under normal conditions, the current through the neutral
wire is nearly zero. *That's because the 180 degree phase difference
between each phase cancels the current in the neutral wire. *However,
with only one phase powered, you're likely to see the full current
through the neutral. *If you're creative and parallel both phases,
then the neutral current is even higher. *Code compliant wiring can
survive this, but I've seen a few blown neutrals. *That's when the
neutral wiring was rotten, and nobody noticed until the full current
was applied.

Another problem is that when you back feed a single wall outlet with a
suicide cord, you're going to be limited by the current limit of the
connected circuit breaker. *In the US, that's about 15A. *That should
be sufficient for most loads, but I suggest to disconnect the high
current loads to prevent blowing the breaker.


Probably the cheapest way to transfer significant load is to wire the
generator to a breaker in the service panel and use a mechanical
interlock:
http://www.interlockkit.com/CATALOG2008.pdf
These prevent both the generator breaker and service disconnect from
being on at the same time. They are NEC compliant. (The generator
breaker is back-fed and the NEC requires a device from the
manufacturer that prevents the breaker from coming out.)

Generator-to-breaker without the interlock is a serious code violation
and not safe.

A safe (and code compliant) way to make a temporary generator
connection to the building is to install an "inlet" fitting on the
building connected to the generator breaker.
http://www.google.com/products/catal...let+receptacle
&oe=utf-8&rls=org.mozilla:en-USfficial&client=firefox-a&as_qdr=y15
&um=1&ie=UTF-8&tbm=shop&cid=13690361079853906458
&sa=X&ei=QtbwTsCMG-mDsgLz6PiXAQ&ved=0CFsQ8wIwAQ
Use the appropriate rating. The prongs are never live since the
generator breaker is never on except when the service breaker is off.
A cord from the generator plugs into the inlet.

I would never wire anything ahead of the service disconnect. Nesesu
described what can happen with a "fault", and his was not directly off
the service wires. Even if fuses were used they would have to be rated
for the "available fault current". Other fuses would give the same
result nesesu got.

--
bud--

On Sat, 17 Dec 2011 11:50:16 -0800 (PST), nesesu
wrote:

On Dec 17, 10:59*am, klem kedidelhopper
wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit *that would indicate the presence of voltage.
For instance I carry a *little "pen" shaped device *in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

Neil S.
I did some rough calculations with this, and it doesn't look good.

The recommended resistance for an NE2 on a nominal 220V line is 220
Kohm. You are suggesting using capactive reactance instead of a
resistor. That is valid for a fixed frequency signal like a power
line.

Using the equation for capacitive reactance, you need 0.01µF - not a
very big capacitor. I've got a bag of .01µF 1KV ceramic caps sitting
on my desk (for another project I STILL haven't gotten to), they are
about 3/8" in diameter and 1/16" thick.

Now the calculations get a little dicey. First some big assumptions.
200A service entrance, whiich requires 000 gauge wire, and a couple of
real SWAG guesses of insulation 0.1" thick, said insulation having a
dielectric constant of 1.

000 guage wire has a diameter of .4", so a diameter of 1.25". That
means caovering a 8" long piece of wire with foil will give a
capacitance of 22pF. You would need to cover about 300' of wire with
aluminum foil.

PlainBill

On Dec 20, 5:10*pm, wrote:
On Sat, 17 Dec 2011 11:50:16 -0800 (PST), nesesu





wrote:
On Dec 17, 10:59*am, klem kedidelhopper
wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit *that would indicate the presence of voltage.
For instance I carry a *little "pen" shaped device *in my tool box.. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

Neil S.

I did some rough calculations with this, and it doesn't look good.

The recommended resistance for an NE2 on a nominal 220V line is 220
Kohm. *You are suggesting using capactive reactance instead of a
resistor. *That is valid for a fixed frequency signal like a power
line.

Using the equation for capacitive reactance, you need 0.01µF - not a
very big capacitor. *I've got a bag of .01µF 1KV ceramic caps sitting
on my desk (for another project I STILL haven't gotten to), they are
about 3/8" in diameter and 1/16" thick.

Now the calculations get a little dicey. *First some big assumptions.
200A service entrance, whiich requires 000 gauge wire, and a couple of
real SWAG guesses of insulation 0.1" thick, said insulation having a
dielectric constant of 1.

000 guage wire has a diameter of .4", so a diameter of 1.25". *That
means caovering a 8" long piece of wire with foil will give a
capacitance of 22pF. *You would need to cover about 300' of wire with
aluminum foil.

PlainBill

Uh, the capacitance limits the current, you don't need a resistor. You
only need the resistor if you directly connect to the 220V

wrote:

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

That looks like a reasonable monitoring action except that when you are
dealing with the incoming line that has no protection, you have to be sure
that whatever you connect across it does not short or catch on fire in the
long run... Aside from that, You only need to monitor one 115v side to
determine whether the power is gone. I suggest you try various physical
"capacitors" by connecting them in series with the NE-2. A 50' extension
cord would provide maybe 2500 pF (.00025 uF), which may be enough to dimly
light that lamp. For instance, with the 50' extension coil disconnected and
laying on the floor, using a plug pigtail, connect the common or ground
house wire to one lead of the NE-2. Connect the hot house wire to the hot
line of the 50' extension cord. the capacitance of the 50' coil should
supply enough brightness to be seen in a dark room.

Even simpler still and a lot safer, buy any extension cord that has a
neon light built into one end. Install it in your favorite house room. Plug
it in and hang the lit end anywhere in sight.

Ange

On Tue, 20 Dec 2011 18:14:54 -0800 (PST), Robert Macy
wrote:

On Dec 20, 5:10*pm, wrote:
On Sat, 17 Dec 2011 11:50:16 -0800 (PST), nesesu





wrote:
On Dec 17, 10:59*am, klem kedidelhopper
wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit *that would indicate the presence of voltage.
For instance I carry a *little "pen" shaped device *in my tool box. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

Neil S.

I did some rough calculations with this, and it doesn't look good.

The recommended resistance for an NE2 on a nominal 220V line is 220
Kohm. *You are suggesting using capactive reactance instead of a
resistor. *That is valid for a fixed frequency signal like a power
line.

Using the equation for capacitive reactance, you need 0.01µF - not a
very big capacitor. *I've got a bag of .01µF 1KV ceramic caps sitting
on my desk (for another project I STILL haven't gotten to), they are
about 3/8" in diameter and 1/16" thick.

Now the calculations get a little dicey. *First some big assumptions.
200A service entrance, whiich requires 000 gauge wire, and a couple of
real SWAG guesses of insulation 0.1" thick, said insulation having a
dielectric constant of 1.

000 guage wire has a diameter of .4", so a diameter of 1.25". *That
means caovering a 8" long piece of wire with foil will give a
capacitance of 22pF. *You would need to cover about 300' of wire with
aluminum foil.

PlainBill

Uh, the capacitance limits the current, you don't need a resistor. You
only need the resistor if you directly connect to the 220V
Do the math. You can't get enough capacitance by using any reasonable
size piece of foil.

PlainBill

On Tue, 20 Dec 2011 22:10:21 -0500, "Angelo Campanella"
wrote:


wrote:

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

That looks like a reasonable monitoring action except that when you are
dealing with the incoming line that has no protection, you have to be sure
that whatever you connect across it does not short or catch on fire in the
long run... Aside from that, You only need to monitor one 115v side to
determine whether the power is gone. I suggest you try various physical
"capacitors" by connecting them in series with the NE-2. A 50' extension
cord would provide maybe 2500 pF (.00025 uF), which may be enough to dimly
light that lamp. For instance, with the 50' extension coil disconnected and
laying on the floor, using a plug pigtail, connect the common or ground
house wire to one lead of the NE-2. Connect the hot house wire to the hot
line of the 50' extension cord. the capacitance of the 50' coil should
supply enough brightness to be seen in a dark room.

Even simpler still and a lot safer, buy any extension cord that has a
neon light built into one end. Install it in your favorite house room. Plug
it in and hang the lit end anywhere in sight.

Ange
Do the math. You need 10,000pF at 220 volts, roughly double that at
120 volts to drive a NE2 lamp to full brightness. Treat it like a
parallel plate capacitor; the formula isC= K*0.2248*A/d. K is the
dialectric constant (most materials have a dielectric constant between
1 and 10), A is the area of the plates, d is the distance between the
plates.

If you wrap foil around a 000 Ga insulated wire you will be getting
roughly 1 square inch of capacitive area per linear inch of cable.
Heavy gauge extention cord has 14 Ga wire, being generous you will be
getting .06 square inches of capacitive area per linear inch of the
cord.

PlainBill

On Dec 20, 7:10*pm, wrote:
On Sat, 17 Dec 2011 11:50:16 -0800 (PST), nesesu



wrote:
On Dec 17, 10:59*am, klem kedidelhopper
wrote:
Our area suffers from frequent blackouts, and many people including
myself use generators, (manually) during these periods. It would be
really helpful to know when the utility side of the circuit is once
again live so that I can put the generator away. Basically I need to
monitor the entrance cable side ahead of the main.
I thought about the simplest way which would be to wire a small NE2
neon lamp across the 240, ahead of the main, (with the appropriate
series resistor of course). The lamp would be lit all the time there
is utility supplied power and off during a blackout. The plan is to
not have to uselessly be running my generator after power unbeknown to
me is restored. The down side of this if it is really any concern
would be that this lamp, small as it as well as its associated wiring
would be would not be protected by a breaker.
The lamp is of course the simplest way, but I was wondering if there
is some sort of inductive circuit someone may know of that that would
not require that current be flowing through a conductor, basically a
circuit *that would indicate the presence of voltage.
For instance I carry a *little "pen" shaped device *in my tool box.. I
press and hold an on button and the unit chirps when brought near a
hot AC circuit. It's a great time saver when trouble shooting a job,
but can something like this be implemented as a full time monitor
circuit? It could be powered off small rechargeable batteries and
always indicate the state of the entrance cable. Thanks, Lenny

Lenny, try taking a plain NE-2 with no resistor and connecting about a
foot of insulated #22 solid insulated wire to one lead and wrapping
that around a piece of insulated wire the same size as your service
entrance wire and connecting the other lamp lead to neutral. Energise
the heavy wire with 120V and see if the NE-2 glows just from the
capacitance of the large wire to small wire. That is about as simple
as it gets and is adequately insulated from the service cable to not
need any current protection.

Neil S.

I did some rough calculations with this, and it doesn't look good.

The recommended resistance for an NE2 on a nominal 220V line is 220
Kohm. *You are suggesting using capactive reactance instead of a
resistor. *That is valid for a fixed frequency signal like a power
line.

Using the equation for capacitive reactance, you need 0.01µF - not a
very big capacitor. *I've got a bag of .01µF 1KV ceramic caps sitting
on my desk (for another project I STILL haven't gotten to), they are
about 3/8" in diameter and 1/16" thick.

Now the calculations get a little dicey. *First some big assumptions.
200A service entrance, whiich requires 000 gauge wire, and a couple of
real SWAG guesses of insulation 0.1" thick, said insulation having a
dielectric constant of 1.

000 guage wire has a diameter of .4", so a diameter of 1.25". *That
means caovering a 8" long piece of wire with foil will give a
capacitance of 22pF. *You would need to cover about 300' of wire with
aluminum foil.

PlainBill

So then if you are capacitively coupling to the main it will require
some type of amplification to activate a signal of some kind. My
little "pen" I mentioned earlier blinks and beeps when held near a
live line. I have never opened it but it runs off a small button cell
of some kind. I haven't tried the inductive, (wrapping the probe wire
around one leg of the entrance cable) method yet.

Years ago I designed a little circuit to monitor compressor run time
on a refrigerator. A small coil was wound around one of the wires to
the compressor. That pickup coil, through a step up transformer
introduced sufficient signal into the input of a UA709. The output
turned on a relay driver which ran an elapsed time indicator. I
thought of trying to modify that circuit to include rechargeable
battery back up, modify the pickup, different turns ratio on the
transformer etc. However depending on what was on in the house when
power failed, the total load would always be different. I never try to
run my electric stove, well pump or electric hot water heater from the
generator. However once utility power is restored they would need to
be turned back on. Only one thing would be certain though. After an
extended blackout the chip would be blasted with an overload. So
trying to implement this old circuit doesn't seem feasible. I suppose
I probably ought to look more at the capacitive "pen"approach too.
Does anyone know exactly what is inside that little "pen"? Lenny

On Fri, 23 Dec 2011 07:34:25 -0800 (PST), klem kedidelhopper
wrote:

I suppose
I probably ought to look more at the capacitive "pen"approach too.
Does anyone know exactly what is inside that little "pen"? Lenny

Look on your pen and see if there's a patent number. Then search for
the patent with google:
http://www.google.com/patents?hl=en
There's usually a schematic or at least a block diagram.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

I probably ought to look more at the capacitive "pen"approach, too.
Does anyone know exactly what is inside that little "pen"?

I believe they use a FET to drive a lamp or other indicator. As FETs (can)
have a very high input impedance, it's possible to pick up 60Hz AC through
capacitive coupling.

On Fri, 23 Dec 2011 08:47:43 -0800, Jeff Liebermann
wrote:

On Fri, 23 Dec 2011 07:34:25 -0800 (PST), klem kedidelhopper
wrote:

I suppose
I probably ought to look more at the capacitive "pen"approach too.
Does anyone know exactly what is inside that little "pen"? Lenny

Look on your pen and see if there's a patent number. Then search for
the patent with google:
http://www.google.com/patents?hl=en
There's usually a schematic or at least a block diagram.

Foundit.
http://www.google.com/patents/US5877618
Schematic in sheet #4. No FET on the input stage. It uses a 4069
CMOS hex inverter through a 10Meg resistor. Cheap.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS

"Jeff Liebermann" wrote in message
...

http://www.google.com/patents/US5877618
Schematic in sheet #4. No FET on the input stage. It uses
a 4069 CMOS hex inverter through a 10M resistor.

Uh... CMOS uses MOSFETs.

On Sat, 24 Dec 2011 04:11:49 -0800, "William Sommerwerck"
wrote:

"Jeff Liebermann" wrote in message
.. .

http://www.google.com/patents/US5877618
Schematic in sheet #4. No FET on the input stage. It uses
a 4069 CMOS hex inverter through a 10M resistor.

Uh... CMOS uses MOSFETs.

Yes, but you said "a" FET which I read as a single JFET or MOSFET used
as an analog 60Hz amplifier. The CMOS gate has far more than one FET
in the input stage.

Pedantic-R-Us

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"Jeff Liebermann" wrote in message
...
On Sat, 24 Dec 2011 04:11:49 -0800, "William Sommerwerck"
wrote:
"Jeff Liebermann" wrote in message
.. .

http://www.google.com/patents/US5877618
Schematic in sheet #4. No FET on the input stage. It uses
a 4069 CMOS hex inverter through a 10M resistor.

Uh... CMOS uses MOSFETs.

Yes, but you said "a" FET which I read as a single JFET or MOSFET
used as an analog 60Hz amplifier. The CMOS gate has far more than
one FET in the input stage.

Pedantic-R-Us

mumble-mumble grumble

On Dec 24, 9:59*am, "William Sommerwerck"
wrote:
"Jeff Liebermann" wrote in message

...

On Sat, 24 Dec 2011 04:11:49 -0800, "William Sommerwerck"
wrote:
"Jeff Liebermann" wrote in message
.. .
http://www.google.com/patents/US5877618
Schematic in sheet #4. No FET on the input stage. It uses
a 4069 CMOS hex inverter through a 10M resistor.
Uh... CMOS uses MOSFETs.
Yes, but you said "a" FET which I read as a single JFET or MOSFET
used as an analog 60Hz amplifier. *The CMOS gate has far more than
one FET in the input stage.
Pedantic-R-Us

mumble-mumble grumble

LOL !!!

a) Some transfer switches are whole-house, being the first
step downstream from the meter.

b) Others are fed by the main panel, and feed a subpanel of
priority loads.

In the case of A, there is a specific metering tap to go to the
line monitoring, even if that's solely a "LINE POWER" lamp.

In either case, stupidity like suicide cords should be
tossed.


--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433