Type S RCD Polarity Clarification

sirsparkalot · Mar 14, 2024

Given the RCD pictured below

[ElectriciansForums.net] Type S RCD Polarity Clarification

With the manufacturers instructions here:

Am i right in interpreting that as well as being able to bring the incoming feeds into the bottom, i can also switch the LIVE and Neutral sides over, so that this arrangement would be possible? Forigve the crudity of the drawing

The thing that gives me some doubts is the manufactures stamp on the RCD on the top left.

pc1966 · Mar 14, 2024

Yes, it seems the RCD is symmetric in both ways so it could be used like you show.

However, would it not be better to take the supply from the busbar via your 50A MCB and then you can wire the delay RCD up the normal L/N way?

Top/bottom feed is immaterial here as the MI says, however, keeping L wire to the L-marked terminal is in keeping with the "principle of least astonishment".

sirsparkalot · Mar 14, 2024

Yeah, you make a good point, i'm so used to switches/protection/surge on the right and overcurrent to their left it didnt even enter my brain until you said it lol.

Saves scraping of the L and using a sharpie on the other side..

mainline · Mar 14, 2024

sirsparkalot said:
Yeah, you make a good point, i'm so used to switches/protection/surge on the right and overcurrent to their left it didnt even enter my brain until you said it lol.

Saves scraping of the L and using a sharpie on the other side..

Just out of curiosity has that tnc-s earthing

sirsparkalot · Mar 14, 2024

mainline said:
Just out of curiosity has that tnc-s earthing

TT at this board, and a separate earth rod at the end of the SWA, swa earthed to main board and not the remote CU.

GroovyG · May 13, 2024

Your drawing suggests that you might be modifying the DB beyond the manufacturer's design specification. If so, this could see you in breach of 536.4.203 so that you effectively become the manufacturer of the complete assembly with its attendant liabilities.