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Pig tail socket.

Tie one side of the pig tail to the faulted line other to the CB, the bulb will light, when you clear the fault the bulb goes out.

Not the safest way to locate faults.
 

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Any of u guys ever use the lightbulb in series trick?

Ive seen it done but never used it?

Someone care to explain it
All the time. Basically the way I do it is divide and concur until the light goes out. Also when an amp clamp is used the current after the fault is always zero, before the fault its what ever the bulb is pulling. Speeds up pinpointing the fault. The method however works only on bolted faults, phase neutral or phase ground. Remember to unplug any loads on the circuit as well.
 

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Always use the light bulb method to locate shorts in 120 volt plant control circuits. Many plants have as many as 3 to 400 field devices. Connect pigtail socket with bulb in series with the control circuit overcurrent device. Start disconnecting field devices until bulb is not at full brightness. Bulb on bright=short is present. Bulb on less than full brightness=short cleared and bulb in series with a normal load. The CC control fuses that we normally use cost around $10 each. Don't want to go through a box of those trying to locate a short.
 
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