10mA RCD for bathroom circuits

kingeri · May 18, 2019

Been to look at a job this morning for a CU change, customer the type who wants to have his say on every tiny detail. He has already bought the CU as well, a Wylex RCBO unit.....

I pointed out that the RCBO ratings he has bought don't align with what I actually need...and that some will need to be swapped. So far, so good.

He then says he wants to include 10mA RCD protection for all circuits in the bathroom. This will be lighting, shower and spa bath pump. I point out that I don't think Wylex do 10mA RCBOs....and if they do why hasn't he bought them instead of 30mA ones...to which he said he why can't I add the 10mA after the RCBOs. I tried to tell him that having two RCDs in series isn't great as they won't discriminate and in this case would actually be pointless. I also said that 30mA protection is the accepted standard for this job. Nevertheless, he still wants it.

I told him I'll be back next week, but he gave me a headache. Just wondered what any of you guys would do in this situation?

buzzlightyear · May 18, 2019

kingeri said:
the chap said he got the idea from a relative who lives in Spain. Maybe they use them over there.

no chance of 10ma everything is 30ma over in tomato land .

kingeri · May 18, 2019

Charlie_ said:
I’ve only used them for equestrian installations

Yes I understand that is an application for them. Never done anything like that myself.

Pete999 · May 18, 2019

Pete999 said:
Your customer will be onto you for every little thing, all OK for call outs bur will become a nuisance to you, if you can put up with that then go ahead, if not and you value your sanity, walk.

Sorry to say this Mate "bad idea to agree to let the customer supply parts in the first place"

The Ghost · May 18, 2019

I would make polite excuses and walk on that one no doubt about it.

kingeri · May 18, 2019

Pete999 said:
Sorry to say this Mate "bad idea to agree to let the customer supply parts in the first place"

I never would agree to this unless it was a light fitting or something. He just produced the CU when I got there.

Toneyz · May 18, 2019

Price the job as per BS7671 using 30mA slightly higher than you usually do (not too high that you would be ripping him off) and make it clear that it is with 30mA only.

The Ghost · May 18, 2019

You would be forever trying to sort out nuisance tripping.

richy3333 · May 18, 2019

Hager used to, and I think still do 10mA RCBO’s

Id tell the bloke the truth - that you’re not doing the work coz he’s an arse, otherwise he’ll go through life not knowing it

SparkyAndGeorge · May 18, 2019

If any doubt, walk away.

James · May 18, 2019

I would politely become far too busy to take on the job.

Tony Reidy · May 19, 2019

kingeri said:
Been to look at a job this morning for a CU change, customer the type who wants to have his say on every tiny detail. He has already bought the CU as well, a Wylex RCBO unit.....

I pointed out that the RCBO ratings he has bought don't align with what I actually need...and that some will need to be swapped. So far, so good.

He then says he wants to include 10mA RCD protection for all circuits in the bathroom. This will be lighting, shower and spa bath pump. I point out that I don't think Wylex do 10mA RCBOs....and if they do why hasn't he bought them instead of 30mA ones...to which he said he why can't I add the 10mA after the RCBOs. I tried to tell him that having two RCDs in series isn't great as they won't discriminate and in this case would actually be pointless. I also said that 30mA protection is the accepted standard for this job. Nevertheless, he still wants it.

I told him I'll be back next week, but he gave me a headache. Just wondered what any of you guys would do in this situation?

Walk away, customers who think they know better are nothing but trouble

PEG · May 21, 2019

He sounds like he is on top of his specification...let him crack on. He can use the same methods he used,for the CU,to find the RCD he needs.
He probably will find someone to take on his project,so let them have all the fun and glory

Toneyz · May 21, 2019

I could not see a 10mA RCBO on their online catalogue.

Michaelp · May 21, 2019

I used 10mA before.Was legrand rcd use for a workbench area

freddo · May 21, 2019

I turned an old Wylex 10mA RCD into an RCD socket by punching a round hole in it and fitting an MK panel socket. I use it a lot for on site appliance repairs where I'm poking inside live appliances. Not as good as, but more practical to carry than a large isolation transformer, and better than nothing.