Insulation resistance quality of an electrical system degrades with time, environment condition i. Megger working pdf Display :- A digital display to show IR value in digital form. Wire leads :- Two nos of wire leads for connecting megger with electrical external system to be tested. Selection switches :- Switches use to select electrical parameters ranges.
Indicators :- To indicates various parameters status i. For Example Power, hold, Warning, etc. IR value is digital type, easy to read. One person can operate very easily.
Works perfectly even at very congested space. Analog display: – Analog display provided on front face of tester for IR value recording. Wire Leads :- Used same as in electronic tester i. For connecting tester with electrical system. No external source required to operate.
Accuracy is not up to the level as it’s varies with rotation of crank. Require very stable placement for operation which is a little hard to find at working sites. Unstable placement of tester may impact the result of tester. Control coil : Connected parallel to the generator, mounted at right angle to each other and maintain polarities in such a way to produced torque in opposite direction. Pointer : One end of the pointer connected with coil another end deflects on scale from infinity to zero. 500 Volt DC is sufficient for performing test on equipment range up to 440 Volts. 1000V to 5000V is used for testing for high voltage electrical systems.