Hello,
Can RCBOs trip if their integral neutral lead is too long?
Went to look at a tripping problem for a customer today, he had a lighting circuit and an alarm system connected to RCBOs that have started tripping.
As you will all know, an RCBO has terminals for the circuit live and neutral, as well as its own neutral that goes to the neutral bar. When I arrived, I found the RCBO neutrals for these two circuits disconnected and taped. I did a quick check by disconnecting the circuit neutrals and putting them directly into the neutral bar in the board, both circuits worked fine, as soon as I put the circuit neutrals back into the RCBOs and put the dedicated RCBO neutrals into the bar, which is how they should be configured, the circuits started tripping.
I noticed that the other circuits, sockets, immersion heater, etc. were also on RCBOs, but the dedicated neutrals for them had all been shortened. It was only the two with long neutral leads that were tripping. I asked the customer’s permission to shorten them to the same length as the ones on the other RCBOs, but he refused; I couldn’t argue with him as it was his property.
Thanks for any advice.
