Circuit Sorting

[BeeJ]

Electrical circuit problem.

Power at the distant location is off caused by unknown circumstances.
Probing with a meter and light bulb (since it draws current) I can go
back in the string to all the places where there is no power. Yes, I
checked the meter and the bulb first and last.
However, when I jump from the circuit point where there is no power
closest to the breakers, I find that all the breakers are ON and there
is the correct potential on the bus-bar and on the output side of the
breaker to the neutral bus-bar.

There are GFIs on some of the circuits found not related to the failed
circuit.
Just to make sure that a GFI was not tripped or the output side of a
GFI was not open, I verified they all tested OK as well as checking the
output side of all GFIs to find them all at 120VAC.

I also checked the hot and neutral to ground on the failed circuit and
found no voltage there.

So, there seems to be an open someplace that I cannot identify.

What is the best way to proceed to troubleshoot this?
All points from the last know dead outlet to the breaker box are buried
in the walls.

Is there a recommended tracer device that will allow me to trace the
unpowered 120VAC circuit (the ones that I have seen need 120VAC at the
socket to power the "buzzer".

Any suggestions are welcome.

 

[Ecnerwal]

Electrical circuit problem.

Power at the distant location is off caused by unknown circumstances.
Probing with a meter and light bulb (since it draws current) I can go
back in the string to all the places where there is no power. Yes, I
checked the meter and the bulb first and last.
However, when I jump from the circuit point where there is no power
closest to the breakers, I find that all the breakers are ON and there
is the correct potential on the bus-bar and on the output side of the
breaker to the neutral bus-bar.

There are GFIs on some of the circuits found not related to the failed
circuit.
Just to make sure that a GFI was not tripped or the output side of a
GFI was not open, I verified they all tested OK as well as checking the
output side of all GFIs to find them all at 120VAC.

I also checked the hot and neutral to ground on the failed circuit and
found no voltage there.

So, there seems to be an open someplace that I cannot identify.

What is the best way to proceed to troubleshoot this?
All points from the last know dead outlet to the breaker box are buried
in the walls.

Is there a recommended tracer device that will allow me to trace the
unpowered 120VAC circuit (the ones that I have seen need 120VAC at the
socket to power the "buzzer".

Any suggestions are welcome.

Your convoluted description can be boiled down to: there is voltage
where the breaker connects to the wire at the breaker box, and there is
no voltage at the first outlet...Thus, the problem would be in that
wire. Unless you have a live outlet you failed to mention between the
dead outlet and the breaker box, in which case the problem is between
the dead outlet and the live outlet. The fact that it's in the wall
simply means that you have to fix drywall to fix (likely replace) the
wire. Start ripping the walls open - or double check the actual
connection of the breaker to the wire, and the circuit neutral to the
neutral bus-bar. ie, make sure you have voltage there when you connect
to the WIRES of the circuit, not just the bus bar and breaker terminal
(unless you do have a live outlet, in which case the connection at the
breaker panel is working.)

The fact that this is confusing to you might mean an actual electrician
would be a good idea.

 

[BeeJ]

More of a how does a GFI work question maybe.
I talked to a professional that works for a major restaurant chain and
he told me that the GFI can fail on the output side and not on the
outlet side so it is probably that. But which one of many.

I need a way to trace the wiring so I know what outlets are tied to the
circuit otherwise I will be opening all the walls .. not a good
solution!

The last outlet I found may not be the one closest to the panel.

So is there a Fox and Hound that can work on a powered or unpowered
circuit?

 

[ehsjr]

Electrical circuit problem.

Power at the distant location is off caused by unknown circumstances.
Probing with a meter and light bulb (since it draws current) I can go
back in the string to all the places where there is no power. Yes, I
checked the meter and the bulb first and last.
However, when I jump from the circuit point where there is no power
closest to the breakers, I find that all the breakers are ON and there
is the correct potential on the bus-bar and on the output side of the
breaker to the neutral bus-bar.

There are GFIs on some of the circuits found not related to the failed
circuit.
Just to make sure that a GFI was not tripped or the output side of a GFI
was not open, I verified they all tested OK as well as checking the
output side of all GFIs to find them all at 120VAC.

I also checked the hot and neutral to ground on the failed circuit and
found no voltage there.

So, there seems to be an open someplace that I cannot identify.

What is the best way to proceed to troubleshoot this?
All points from the last know dead outlet to the breaker box are buried
in the walls.

Is there a recommended tracer device that will allow me to trace the
unpowered 120VAC circuit (the ones that I have seen need 120VAC at the
socket to power the "buzzer".

Any suggestions are welcome.

When some (all?) breakers trip they can look like they are
still on. The least invasive repair action you can perform
is to flip the breakers off, then back on. That will reset
a tripped breaker, if there is one. After you have done that,
if the problem still persists, reset all the GFIs. If that
doesn't fix it, read on.

Your description is not clear, so giving more specific
recommendations is difficult. In general, you need to identify
which breaker controls the circuit with the problem, and
determine everything that is on that circuit. GFIs on
other circuits have no bearing on the problem; a GFI on
the failing circuit may need to be reset. Your problem
lies at the last properly working location, or the first
failing location, or between those locations.

If the wiring was done properly there will be *no* connections
buried in the walls. All connections are required to be made
in junction boxes, and the covers for those boxes are required
to be accessible. In very close to 100% of cases, the junction
boxes will house a receptacle, a switch or a connection to a
light or fan. Opening up the walls is NOT required to troubleshoot
this problem. You can, if necessary, open up every junction
point on the failing circuit and check for continuity from
junction point to junction point using an ohm meter.

Ed

 

[Winston]

More of a how does a GFI work question maybe.
I talked to a professional that works for a major restaurant chain and
he told me that the GFI can fail on the output side and not on the
outlet side so it is probably that. But which one of many.

I need a way to trace the wiring so I know what outlets are tied to the
circuit otherwise I will be opening all the walls .. not a good solution!

The last outlet I found may not be the one closest to the panel.

So is there a Fox and Hound that can work on a powered or unpowered
circuit?

I've got no personal experience with this tool but it does
get good reviews:
http://www.harborfreight.com/cable-tracker-94181.html

--Winston

 

[BeeJ]

I spoke with a long time professional electrician that works for a
major restaurant chain and he said the GFIs can fail on the
continuation circuit with no indication at the socket outlet and the
GFI will test OK. GFI have a separate set of contacts for the socket
and the continuation.

Anyway, I am still looking for a Fox and Hound that can work on a
powered or unpowered circuit.

To make matters worse, the dead circuit has turned back on and is fully
functional. No one knows why as everyone says they did not do anything
like reset a breaker or reset a GFI. Bizarre.

 

[BeeJ]

Oh, and I think I said that there is power at the breaker on the output
side. The multimeter reads 118 VAC from breaker output to the neutral
bus.