Breaker finder tool for lighting circuit

[anbm]

We had a project where we will replace existing pole light with new light. There are no as-built drawings.
EC said they could not trace which electrical panel or breaker powers the existing light so they cannot replace the light,
and ask for solution...

Is there a breaker finder tool for lighting circuit in the market? Similar as the one for outlet?
Worst case, I guess first they can meter the circuit to know circuit voltage, then turn off panel by panel
to know which panel powers the pole light, then turn off each breaker in the panel to know which
breaker feeds the pole light circuit??? This could be a day long...

 

[Strathead]

Any good circuit tracer. Search for greenlee cs8000.

 

[kwired]

Use alligator clips and clip onto whatever works on the circuit you are wanting to trace.

If you happen to have Edison base lamp holders in the circuit you want to trace just screw an adapter into it that people use to plug cords into lamp sockets. I have one of those in the box with my tracer, doesn't get used a lot but is handy for this when such conditions come up.

 

[hillbilly1]

There are several good brands of tracers out there, Greenlee, Ideal, and Amprobe just to name a few. There also is cheap brands that will get you to the right panel, and even real close to the right breaker is used exactly as the directions call for, one is Zircon, about $200, but works reasonably well for the price. Not as good as my Amprobe, but if you follow the directions exactly, most of the time you can narrow down to two or three breakers in a panel.
Circuit Breaker Finder: 80 to 300V AC, 71263 ZIRCON, Circuit Breaker Finders, 71263 ZIRCON
https://www.grainger.com/product/56...y.CopyToPasteboard-_-iPhone_IDPShare-_-56HN46

 

[topgone]

We had a project where we will replace existing pole light with new light. There are no as-built drawings.
EC said they could not trace which electrical panel or breaker powers the existing light so they cannot replace the light,
and ask for solution...

Is there a breaker finder tool for lighting circuit in the market? Similar as the one for outlet?
Worst case, I guess first they can meter the circuit to know circuit voltage, then turn off panel by panel
to know which panel powers the pole light, then turn off each breaker in the panel to know which
breaker feeds the pole light circuit??? This could be a day long...

3M makes those circuit tracers. You just clip the two leads on a circuit the 3M signal emitter and then proceed to place the tracer on any line, tracing what it supplies power to. When the tracer gets close to the lines that the emitter is connected to, you'll hear a pulsing beep.

 

[kwired]

The better tracers out there also rated to be connected to at least 300 volts. That does allow you to connect them to 277 volt circuits or even line to ground on a three phase circuit with no neutral, if it is on a 480/277 supply.

 

[gar]

230530-2024 EDT

Put an oscillating load of about 12 A on the circuit for which you are looking. Make ON time 3 seconds, and OFF time 3 seconds. The time can be longer. The 3 seconds is generally long enough to see the change on a digital meter.

Then use a meter to measure the voltage from hot to the load side of a breaker. You will see the pulsing voltage drop across the breaker that feeds th pulsing load.

.

 

[kwired]

230530-2024 EDT

Put an oscillating load of about 12 A on the circuit for which you are looking. Make ON time 3 seconds, and OFF time 3 seconds. The time can be longer. The 3 seconds is generally long enough to see the change on a digital meter.

Then use a meter to measure the voltage from hot to the load side of a breaker. You will see the pulsing voltage drop across the breaker that feeds th pulsing load.

.

Or put a 40 amp load on it and just wait for the breaker to trip (for 15 and 20 amp circuits and of course non FPE, Zinsco, etc.)

 

[hillbilly1]

We had a project where we will replace existing pole light with new light. There are no as-built drawings.
EC said they could not trace which electrical panel or breaker powers the existing light so they cannot replace the light,
and ask for solution...

Is there a breaker finder tool for lighting circuit in the market? Similar as the one for outlet?
Worst case, I guess first they can meter the circuit to know circuit voltage, then turn off panel by panel
to know which panel powers the pole light, then turn off each breaker in the panel to know which
breaker feeds the pole light circuit??? This could be a day long...

Could be a leased utility owned light and pole. They usually just loop a direct burial cable straight off the transformer, with fuses at each pole. I have come behind parking lot upgrades, where the customer paid for the heads to be changed out to LED, without realizing they don’t own the poles or the fixtures! They were only saving the utility money!

 

[don_resqcapt19]

Or put a 40 amp load on it and just wait for the breaker to trip (for 15 and 20 amp circuits and of course non FPE, Zinsco, etc.)

You may be waiting some time if the breaker is in a 25°C ambient and not the 40°C ambient it is rated for. One major brand's trip curve puts the 2x trip time well over an hour if the breaker is in a 25°C (77°F) ambient.

 

[anbm]

Could be a leased utility owned light and pole. They usually just loop a direct burial cable straight off the transformer, with fuses at each pole. I have come behind parking lot upgrades, where the customer paid for the heads to be changed out to LED, without realizing they don’t own the poles or the fixtures! They were only saving the utility money!

Interesting!

 

[hochwire]

Klein ET450 best tracer

 

[hillbilly1]

Klein ET450 best tracer

Never tried that one, but looks to be a good entry level tracer. My Amprobe can accurately find a wire out of a bundle of 100 or more! But then it’s a lot more expensive. It picks up a current pulse instead of injecting a signal, which tends to bleed over with other tracers. The downside is it works only on live circuits, or circuits you can put a voltage loop on, such as a battery.

 

[Ravenvalor]

230530-2024 EDT

Put an oscillating load of about 12 A on the circuit for which you are looking. Make ON time 3 seconds, and OFF time 3 seconds. The time can be longer. The 3 seconds is generally long enough to see the change on a digital meter.

Then use a meter to measure the voltage from hot to the load side of a breaker. You will see the pulsing voltage drop across the breaker that feeds th pulsing load.

.

You can keep one of those tiny space heaters in your truck so as to not take up too much room. If you don't have something that will oscillate a 1500w load you can always get a helper to manually oscillate the load for you.