Hi Is there any objection to replacing MCB's which are already protected by an RCD by RCBO's? If allowed, I'm hoping the RCBO would trip out before the RCD, so only the RCBO circuiit becomes "dead" Kind regards diymostthings
It will be a total gamble which trips out first on each circuit to be honest and if you have any slight earth leakage on the other circuits most likely it will be the main rcd due to a cumulative effect of all the earth leakage going through it.
It's an MK 17th edition split load with two RCD's covering all circuits except 2 which are only protected by an MCB
Hmmm. That's what I feared stu312. Is there ANY advantage then in doing this? kind regards diymostthings
Well although I have split the circuits controlled by the two separate RCD's as recommended it is still inconvenient to have several circuits tripping out when only one is faulty - and it could be any one of the 5 circuits controlled by that RCD which is the faulty one. With an RCBO on each, you would know which circuit is faulty and only that one would trip. So the idea was by way of an upgrade but I wasn't sure if it was practical to buy expensive RCBO's only to find out that the RCD trips anyway. Hence my question. Is there a solution? kind regards diymostthings
Are you currently having problems with the rcd's tripping out? Might be best to get a spark in to trace the fault if you are. I've been using a split load boards for years now and not had any problems.
Was it sold to you as a "High integ dual RCD board" if so there should be 3 neutral bars 1 for each RCD and 1 for the unprotected High integ circuits on which you currently have MCBs. Replacing the MCBs with RCBOs is pefectley standard practice that is often done on installations for ccts like freezers or problem tripping cookers, these RCBOs would be on the seperate neutral bars and should not interfere with the RCD ccts. However as already stated if you have problem tripping then you need a spark to trace the fault as it may not be on the RCD that it appears to be.
Hi folks, I have just bought a Wylex box complete with eight RCBs, to my horror they were those new fangled Wylex NHXSBS1Bs with the white and blue wires sticking out the top!! Does anyone know where they need to be wired to? Thanks
White is functional earth, blue is neutral. The circuit neutral is wired into the RCBO, and the neutral from the RCBO connected to the neutral bar.
Hi thanks for that, I had tried wiring the white to the earth bar and blue to the neutral bar but it tripped as soon as power was required.
Yes it is a Wylex dual RCD board - and I completely understand the earthing busbar requirments. i have no tripping problems - just thinking ahead...
No tripping sinewave - and I have the gear needed to measure Zs and to trace faults. It was a TT to TN-C-S (PME) conversion. I was just thinking ahead to the day when something goes wrong... diymostthings