Earth Fault Loop Impedance testing at Otahuhu

“Earth Fault Loop Impedance testing a 10 amp power point circuit extension!”

You say what? Don’t you love it when tradies talk acronyms in front of customers. BullSh#t baffles brains some say.

So, let’s break this down for you and take the bull out of the sh#t.

Main reason why this test is conducted is to ensure the following;

1. Will the circuit breaker or fuse trip/blow and clear the fault?
2. Will the circuit breaker or fuse trip/blow in time?

Failure to do this test on active power circuits before extending and or modifying the circuit could potentially lead to property damage though fires or electrocution due to the circuit breaker not tripping/blowing due to incorrect cable sizes suppling the power circuit over a long distance.

Results of Testing

Result of the test conducted for Otahuhu Business Association (OBA) required an extension to the power circuit to supply interactive display board.

On investigation the cable sizing was 2.5mm two core plus earth tough plastic sheath known to us sparkles as a 2.5mm 2C+E CU TPS.

Testing was conducted using a Calbrated Fluke 1664 Multifunction Tester using the meter set on Z Ohms Loop Impedance test. The following results were obtained 1.72 ohms @ 135 amps on a 79 meter cable run on a C16A miniature circuit breaker.

Published date: 12 May 2022