littlespark

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I'm not being stupid here. Not correctly, as in, not as the labels on the device says

So, the situation is, I have a TP&N distribution board with a regular 125A 4 pole mainswitch. The terminals serve in order- N, L1, L2, L3 with the neutral on the left.
This installation is to have a 300mA RCD mainswitch fitted.
The manufacturer of the distribution board can supply the RCD, but the connections are marked 1,3,5,N on top and 2,4,6,N on bottom. ie, the neutral is on the right of the switch module.

The paperwork with the RCD says that the load and supply can be reversed.. ie, fit the thing upside down, but that's not going to look great.

It also says that the RCD can work as a 2 pole device using 1-2 (not 3-4 and 5-6)and the N, and these can be reversed. (putting live into the N terminal, and neutral on the 1-2 poles)
If so, can I do it this way and still use the other 2 phases in the middle terminals?

I have already asked the manufacturer for their technical advice and await their reply. You lot are much quicker.

How does a TP&N RCD work and will it work if I connect it up the way I need to?
Will I need to add a new enclosure before the board with the RCD in it, with the cables in the right positions?
I know the answer to this one, but can I ask the fairies to pull the fuses and i'll put the rcd in place of the suppliers isolator

I'll post photos of the equipment when I have some. My description isn't too clear now I've read it over.
 
who's board is it?
 
Board design changed last year alone with order or main switch connections as I had the same issue. Did your wholesaler sell you an older board?
 
As far as I’m aware, with TP&N RCDs, all conductors pass through the coil.
As long as they’re in balance the RCD doesn’t operate.
As such, it should not matter which way round the conductors are connected.
 
The RCD operation itself, as far as detecting imbalance, should work any which way. But if the contacts are sequenced, it is important on a TP+N system that the neutral is connected to the N pole of the device, so that the lines are never connected without it.
 
Was thinking simultaneous operation due to the manufacturer’s stating the device can be used for double pole operation, with the neutral in either pole.
 
Hmm. Conflicting opinions there.
Still waiting for contactum technical to get back to me.
In the meantime, a photograph of the RCD itself. Hard to see the terminal markings, but you can see the schematic diagram if you zoom in.
2611AA61-9985-45B9-AF79-52C7ED45E2F3.jpeg

I’m thinking it doesn’t matter, but I don’t want to test the theory without a little back up.
 
as long as contrectum email you that it's OK, your arse is covered.
 

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littlespark

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If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
United Kingdom
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Practising Electrician (Qualified - Domestic or Commercial etc)

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Title
Does a TP&N RCB work if not connected correctly?
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Commercial Electrical Advice
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