Megger is a brand that became the trade word for an insulation resistance tester, which applies 250 to 1000 V DC or more between conductors and to ground and reads leakage in megohms. Electricians megger new feeders and motor circuits before energising and check suspect wiring after water damage, expecting hundreds of megohms on new work. Anything electronic on the circuit, from drives to dimmers and surge devices, gets disconnected first.
Heard on the job
Megger the feeders before we land them, a thousand volts phase to phase and to ground, and log the numbers.
Also heard as
- megohmmeter
- IR tester
- insulation tester