Sending food back to the kitchen?

[CallumWK]

I have followed @carlyai thread with interest, as I have a similar issue, in my maid's quarters.

The maid's quarters is about 30 meters from the house and fed by an underground cable coming from the main house, and on a circuit that has a 63A RCCB.

 

MQ has never been occupied, and for the last few years the RCCB in the house tripped maybe once every few months, which I attributed to the pool pumps being on the same circuit. But when I closed the RCCB again, all would be fine.

About a month ago it tripped during heavy rain, and then I found out that the issue was in the MQ, because I couldn't close it until I opened the MCB to the MQ. I left it like that for more than a week, but then the problem still existed, so I started checking.

 

In the MQ there is a 2 pole 40A MCB (ABB S202M) and 5 single MCB's. Unfortunately, the breakers are not marked which circuit they cover.

Everything is switched off, I switch 2 pole MCB on, no problem. I can switch on MCB 1 and 3 without the RCCB in the house tripping.

Whenever I switch on MCB 2 - 4 or 5 the RCCB trips immediately, and can not be closed unless I open MCB 2 - 4 and 5. As said nothing is active in the MQ, nothing plugged in the sockets either.

 

I already removed all neutrals from the neutral bar, as suggested in the other thread, but that doesn't make a difference.

 

So now I would like to try another RCCB, but I'm not gonna part with 2500 baht for an ABB RCCB, just for testing purposes, so any suggestion on a cheaper/reliable brand are welcome.

 

I should add, the house and MQ have earthed electrics and are 12 years in use.

 

 

 

Edited 2 hours ago by CallumWK