3 Phase and RCD

[NikNak]

We have moved to a house with a 3 phase supply with a Contactum 8 way board.

There are no RCD's for the ring mains and we want to add these how do you go about it as its obvious you can add to the 3 phase board, 4 circuits.

I have some MK Tybe B MCBs and need to add a couple of circuits, can these be used.

I know the additions will need to be signed off.

Many thanks

 

[ricicle]

Can you explain again clearly what you want to achieve

 

[NikNak]

1. To add RCD protection to a residential 3 phase for the ring mains.

2. to add 2 additional circuits using MK Tybe B MCB's

 

[industryspark]

please dont take offence at this but you need a qualified spark to do this job.

it comes under part p.

also 3 phase really isnt a DIY job, the fact that your asking these questions shows to me that you need a spark who is used to three phase.

 

[NikNak]

No offence taken.

I admit I dont know about 3 phase thats why I am asking. I have done a couple of rewires on single phase which have always been signed off at the first attempt.

The 3 phase is set up with all single phase MCBs. No 3 phase outlets fron the board.

I simply want to know how to add RCD protection to the ring mains and to know if my MK Type B MCBs that I have left over can be used in the spare slots.

The council have agreed to inspect for part p.

 

[Belle427]

http://www.tlc-direct.co.uk/Products/CM93203.html
32 Amp 30mA RCBO

 

[industryspark]

in that case,

can you not change the mcb's for the ring circuits for RCBO's ( john D will be happy ive mentioned them! )

not sure about compatibility of mk and contacum, however you could just buy some contactum mcb's for your new circuits ( about 7 squid each!)

 

[securespark]

You say you have a 3 phase supply, then refer to a Contactum 8 way board. This is a 1P board, not 3P...

 

[plugwash]

http://www.tlc-direct.co.uk/Products/CMD08B.html

looks like contactum do a board with 8 three phase ways to me.

seriously though post some pictures of your setup, if you really do have a 3 phase board and want to add RCD protection to some cuicuits then RCBOs are your best bet. Wherever possible you should always stick to the same brand as the board and note that with some manufacturers (notablly MEM) the domestic MCBs won't fit the 3 phase boards.

 

[NikNak]

Thanks all.

Thats the one that we have and it currently has the following for the ring mains which I want to replace, obviously with RCBO's thanks to your advice:

http://www.tlc-direct.co.uk/Products/CM7132B.html

Thanks for all your help.

 

[securespark]

You have to be ultra-careful that adjacent accessible accessories are not on two different phases, unless you have 400V warning stickers on them.

If they are just bog standard 1P breakers, replace them with bog standard 1P RCBO's.

 

[Pensdown]

NikNak, are you 100% sure you've got a 415V 3 phase supply and not just a linked out 3 phase distribution board?

Can you post some pic's because you may have a TT installation which means in some circumstances you can't use single pole RCBO's