415v 3 phase sockets and rcd protection.

[simpson93]

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

 

[westward10]

Hello why do you have a DIY tag on your banner?

 

[simpson93]

Hello why do you have a DIY tag on your banner?

Dunno

 

[westward10]

Are you an electrician?

 

[simpson93]

Are you an electrician?

Yep, memeber of the forum since 2010, seems to be a problem since the site was changed.

 

[westward10]

Yep, memeber of the forum since 2010, seems to be a problem since the site was changed.

Okay should be gone now.

 

[telectrix]

Okay should be gone now.

mod. witchycraft strikes again. .

 

[Charlie_]

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]

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]

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.

 

[Charlie_]

Standard way is no RCD for that type catering equipment

 

[BrendonP]

? But socket outlets up to 32amp require RCD protection. Or is there a way around this ?

 

[davesparks]

Standard way is no RCD for that type catering equipment

Since when?

 

[Charlie_]

Commercial stationary equipment doesn’t need RCD protection.
Since it was first invented

 

[Charlie_]

? But socket outlets up to 32amp require RCD protection. Or is there a way around this ?

Yes there is