rcd as main switch?

[tom1]

and next cu with main switch and lots of rcbo

 

[batty]

That would be unlikely.16th ed CU's (split load) had a main switch that isolated some circuits and also fed an RCD which protected some more circuits.

16th TT CU's had a 100a / 100mA time delay RCD instead of a main switch

17th ed CU's (twin RCD) have a main switch which feed 2 seperate RCD's which protect some circuits each

Also high integrity which has space for a few Rcbo's ie cooker/immersion heater as well as two RCD's

 

[spinlondon]

All circuits in a TT installation must be protected with at least a 100mA RCD.

All socket outlets below 20A must be protected by at least 30mA RCD.

All circuits with cables buried less than 50mm in walls must be protected by at least 30mA RCD.

All circuits in bathroom must be protected by at least 30mA RCD.

You could have an installation where the cabling is all in surface trunking, the sockets and bathroom circuits would have to be on 30mA RCDs, with all the other circuits on the 100mA main switch.

You are required by the Regs. to consider the effects of having more than one circuit on an RCD. There is no requirement to actually place all circuits on separate RCDs.

 

[tom1]

Applaud Smiley

 

[Adrian]

hi, just a quick question can an rcd be used as a main switch? for some reason i think Ive heard you cant but not sure now i said it, any help/advice i will be most greatful.

the simple answer to this is yes

example garage cu with only two circuits

caravan cu

off peak cu

ect ect

not recommended on a domestic cu , but if you read the regs to the letter two rcds do not really comply, but they realised the cost and made this an exemption.