• Welcome to the new forum. We're now hosted on ElectriciansForums.net rather than ElectriciansForums.co.uk - Chat about the forum upgrade by CLICKING HERE

Welcome to our Electrical Forum - We started out providing electrical advice just for the UK - But now we have specific advice for the USA too! - Register for free and share American Electrical Advice.

Discuss 415v 3 phase sockets and rcd protection. in the Electrical Forum area at ElectriciansForums.net

simpson93

Regular EF Member
Afternoon all,

Looking for a little guidance, other than doing sub mains in armoured I don’t do much three phase work.

I’m looking to install some final
Circuits for some three phase cooking equipment but I find myself stuck on a few things, as the sockets will be over 16amp they will need to be rcd protected but I can’t seem to find anything to find a Hager board rcbo etc. What’s the best way to protect it?

Also generally if doing a three phase sub main I would take an additional earth as I’m not so keen on solely relying on the armoured earth. Do most people generally rely on the armoured earth or use 5core?

Thanks for your help
 

Charlie_

Electrician's Arms
I would do 1 of 2 things..
Don’t have the sockets protected by an RCD, subjust to a risk assessment or
Have the appliances hard wired into an isolator, negating the need for RCD protection, subject to installation methods.
You can have an RCD incomer protecting all circuits if necessary..
Have you done any adiabatics?
 

davesparks

Forum Mentor
Also generally if doing a three phase sub main I would take an additional earth as I’m not so keen on solely relying on the armoured earth. Do most people generally rely on the armoured earth or use 5core?
Sockets with RCDs built in are usually more readily available and a simpler solution than three phase RCBO's, these are often made up from add on modules and quite big taking up 6 ways in a DB.

This mostly comes down to the quality of the glands you use and your ability to fit them correctly. If you fit the correct gland properly then there will be no problem.

If fitting standard surface mount commando sockets with the plastic threaded entry there is rarely room to fit an earth connection to the SWA gland. You may need an adaptable box or besa box to gland the SWA to and make the earth connection or use 5 core cable.
 

BrendonP

Active EF Member
For earthing glands i am using earth lock nuts most of the time now.

An example -

WISKA EN20 P NUT 20mm brass locking earth nut PIRANHA - Edwardes - https://www.edwardes.co.uk/en/products/wiska-en20-p-nut-20mm-brass-locking-earth-nut-piranha?utm_medium=google_shopping&utm_source=google&utm_campaign=google_shopping&gclid=Cj0KCQjw-tXlBRDWARIsAGYQAmeN9Z9Jx_4XnSpqMDlLjwq56Hz4Pwu85dzG4rq9lTGRGB_FOPWeUIAaAtpaEALw_wcB

MCB in the board and RCD in the socket outlet is the standard way to do this i believe. Use a socket with a built in rotary isolator takes care of isolation as well.
 

Electrician Talk

Electrical Forum

Welcome to the Electrical Forum at ElectriciansForums.net. The friendliest electrical forum online. General electrical questions and answers can be found in the electrical forum.
Electrical 2 Go - Electrical Supplier and Electrical Wholesalers
Electrical Insurance
ElectriciansForums.net (formerly known as ElectriciansForums.co.uk) was setup in April 2006 to provide free electrical advice to both professional and DIY electricians. Whether seeking advice for auto electrics, trying to find electrical installation condition reports (EICR) form downloads, or whether you're here just to talk to other electricians; we've been a first-choice website for tens of thousands of sparkies for well over a decade.
Top