If I wanted to check the insulation on the wiring that was just pulled to a subpanel how do i do this. It is a single phase panel (two hots a neutal and a ground). If I test each wire between each wire would this tell me if my insulation is good or bad. If so how does it do it if the wires are open on one end? Does the high voltage just look for leaks between each other.
Megger opperation
- Thread starter JdoubleU
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weressl
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Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points, and inversely proportional to the resistance between them. (Wiki)
I=V/R
The Megger generates a preset voltage of 500V or higher. By measuring the current the resistance can be calculated and displayed. The megger is calibrated to read in the high resistance range and built to measure high resistance value, such as insulation value. It is used to determine if your insulation value is high enough for safe and reliable operation of the electrical equipment or wiring.
So indeed you are usually measuring two things:
1./ resistance between the circuit wires, phase-phase, phase-neutral.
2./ between each of the above components and ground.
Consequently you would isolate the circuit wires from the supply and each other before using the megger. You can measure the overall resistance of the entire circuit - lead wires and the driven equipment - versus the ground in a single step.
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zog
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