Discuss Will this RCD fit into this board? in the UK Electrical Forum area at ElectriciansForums.net

HappyHippyDad

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Morning....

I have a chap who wants 30mA protection on all his circuits.

He currently has the main switch as seen in the picture below showing the whole CU
wsem.jpg

Will the RCD below fit into this board in the same place?
wses.jpg
The one he has is marked WSEM, the one I can buy is WSES. Are these interchangeable?

If they are not then I may try and convince him just to have 30mA protection on the circuit I will be working on. So my next question is, is there an RCBO which will fit this board?

Cheers.
 
Having seen another thread I dont think there is an RCBO that fits this board, just an RCCB taking up 2 positions. So it's just the question about whether the WSES and WSEM are interchangeable?

He will not be swayed to fit a new board so that is not an option.
 
Having seen another thread I dont think there is an RCBO that fits this board, just an RCCB taking up 2 positions. So it's just the question about whether the WSES and WSEM are interchangeable?

He will not be swayed to fit a new board so that is not an option.
Well HHD if you can't find a suitable replacement that the Manufacturers agree will be safe to exchange with the one already in situ, and the client won't agree to a CU change you don't have much of an option, do you? time to consider your options for the job. Other than putting in a Main Switch in place of the existing RCD and installing a stand alone RCD to cover the board, in a separate enclosure, I can't see as you can do anything else you can do, with the work involved to use a stand alone RCD +enclosure + tails + Henly blocks would it not be as cheap to swap the board? not done any price comparisons so not sure, worth a coat of looking at though, don't you think?
 
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Ive recently added a new socket to a 3036 board.

Run a suitably sized cable to an external RCD and extend the circuit cables into the enclosure with the RCD in it.
Have done similar, it doesnt add much to the overall cost of the job either, With the 18th coming into effect in the new year then I think we will be doing a lot more of that, especially with light circuits as they are often found without rcd protection. Although I expect some funny customers who will feel we are trying to rob them when dodgy dave down the pub will do it sans rcd for half the price.
 
Cheers all, but does anyone know if the WSES fits in the WSEM? Or are you just politely ignoring that part as its a daft question due to lack of discrimination? :)

I should have perhaps made it more clear that this is specifically what the client has asked for. I could easily add another enclosure by the RCD to give my work 30mA, or I could even just fit a 30mA RCD fused spur by in place of the JB I am pinching the power from, however he wants the 100mA main switch replaced by a 30mA. Will the WSES fit in this board?
 
I believe that they are the same physical configuration.
I am fairly sure I replaced one sometime ago, however I cannot remember if it was 30mA to 100mA or vice versa or just a straight swap, so not much help there!
There is a model that is not compatible, just not quite able to align the rigid neutral bar, but I would have to search through old spares to be able to compare and contrast.
Just tell the customer you need to take the existing one with you to ensure compatibility!!;)
 
If it was an isolator and not an RCD, I would probably agree that it wouldn't comply. But since it's already an RCD and in the event of a fault it will trip and take out everything, I think there is some argument to say it's not making things worse in fact you could argue it's a safety improvement since the whole installation would have additional protection.
 
If it was an isolator and not an RCD, I would probably agree that it wouldn't comply. But since it's already an RCD and in the event of a fault it will trip and take out everything, I think there is some argument to say it's not making things worse in fact you could argue it's a safety improvement since the whole installation would have additional protection.

Think thats stretching the spirit of things a bit. That 100mA might sit there all day, not noticing diddley, whereas the 30mA will trip if there's a Y in the day.
 
Think thats stretching the spirit of things a bit. That 100mA might sit there all day, not noticing diddley, whereas the 30mA will trip if there's a Y in the day.

I did say you could argue it's an improvement... not sure I would :)

I've got a client with one of those boards and when it came to testing some changes, I couldn't even get 1/2x test to complete. Ramp tested the RCD with nothing on it and it was tripping at around 12mA.

Only tripped when I tested it, despite the installation being somewhat old.

The risks could perhaps be mitigated somewhat with a couple of well placed emergency lights.
 
Is this a TT supply this I don't think has been answered which maybe why a 100mA rcd main switch.
What is wrong with it anyway Do you want to change to 30mA for compliance for the works you are carrying out?
 

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