A
aircooled
Just wondered if anyone could help on this one, probably should know it, but in dumb mind today. I have fitted a new split consumer unit in a bungalow. I have connected the existing ring circuit (b/r wiring) to one side of the unit, 32A MCB (on one 63A RCD) and the existing interior lighting to the other side on a 6A MCB (on other 80A RCD). In this set up as soon as power is applied both RCD's trip. If I turn off the MCB for the existing lighting circuit all is ok. If I transfer the existing lighting circuit to the same side as the existing ring circuit on a 6A MCB, it all works fine. The bungalow is 1986 with single story flat roof extension, black and red wiring and had a 13th edition board. I have informed the client of this problem and that I suspect some wiring cross over that is tripping the system. They do not want to pay for any more work. When testing this system before installation nothing showed up, but I was not able to disconnect everything because they have added so much to the system including fixed wired external lighting etc. They also had some work done few years ago to sort a problem with the lighting in the extension, but they were not sure what he did, but he said he had put a fix in.
How I set it up initially
RCD 80 - 40A Shower (new circuit), 16A Garage Radial (new circuit), 6A Interior Lights (existing r/b wiring)
RCD 63 - 32A Cooker (Not used except for ignition of gas cooker/clock), 32A Ring (existing r/b wiring), 6A Exterior Lights (new circuit)
To make it work
RCD 80 - 40A Shower, 16A Garage Radial
RCD 63 - 32A Cooker (Not used), 32A Existing Ring, 6A Existing Exterior Lights, 6A Interior Lights
Wanted to keep the existing ring and existing interior light separate and not put the new shower and existing ring on the same side either.
I suspect the neutral for the original lighting circuit has been borrowed from the existing ring. The other lighting circuit is a new one I put in, was hoping to keep the internal light and the ring separate, but looks like they will have to remain on the same side. As this borrowed neutral is from the existing wiring and could be any where, is it safe to leave it? Just want to make sure it is all ok and safe. Finding the fault and fixing it could take a while and cost money the customer does not want to spend. Everything works ok.
Your advice would be much appreciated. I have tested the RCD and changed the 6A MCB.
I would prefer to find where the problem is and fix, therefore I would appreciate any advice on the best way to find it. I plan to go through every socket, switch and light fitting, but one I did open was a real birds next??
Anyhow any advice would be helpful.
regards
David
How I set it up initially
RCD 80 - 40A Shower (new circuit), 16A Garage Radial (new circuit), 6A Interior Lights (existing r/b wiring)
RCD 63 - 32A Cooker (Not used except for ignition of gas cooker/clock), 32A Ring (existing r/b wiring), 6A Exterior Lights (new circuit)
To make it work
RCD 80 - 40A Shower, 16A Garage Radial
RCD 63 - 32A Cooker (Not used), 32A Existing Ring, 6A Existing Exterior Lights, 6A Interior Lights
Wanted to keep the existing ring and existing interior light separate and not put the new shower and existing ring on the same side either.
I suspect the neutral for the original lighting circuit has been borrowed from the existing ring. The other lighting circuit is a new one I put in, was hoping to keep the internal light and the ring separate, but looks like they will have to remain on the same side. As this borrowed neutral is from the existing wiring and could be any where, is it safe to leave it? Just want to make sure it is all ok and safe. Finding the fault and fixing it could take a while and cost money the customer does not want to spend. Everything works ok.
Your advice would be much appreciated. I have tested the RCD and changed the 6A MCB.
I would prefer to find where the problem is and fix, therefore I would appreciate any advice on the best way to find it. I plan to go through every socket, switch and light fitting, but one I did open was a real birds next??
Anyhow any advice would be helpful.
regards
David
