Size of suppliers fuse vs RCD

[DuncanS]

Here's a scenario, I'm adding two new circuits to a mini consumer unit for my first ever NAPIT inspection... Just noticed that the main switch/RCD is rated to 100amps but the suppliers main fuse is only 80amp, should I change the RCD to one that's 80amp or lower, I don't want the NAPIT spark to think I've over looked anything...
just to add detail the circuits on the board are as follows, oven 32amp breaker! shower 45amp breaker, jacuzzi 20amp breaker.

 

[Sintra]

Its fine so long as it is rated greater than or equal to the max demand. Remember this doesn't provide any form of overcurrent protection.

 

[Plonker 3]

There is a difference between a fuse and a switch. Which you should either know or find out before your assessment.

 

[Knobhead]

This has to be a wind up. If a first year apprentice had asked me that his ears would still be ringing next Saturday.

Assessment? Do you think you are even competent?

 

[telectrix]

sad fact these days, tony, that schoolboy blunders, not knowing the difference between an isolator and a OCPD, are common occurrences with under trained , under qualified, domestic installers. only ones to blame are the scam providers for putting money before safety and the governments that let these parasites continue to operate.

 

[NickD]

(Just dealing with the reality of the way the world is rather than the way we think it ought to be for a second, the guy is here and is asking the question. Does it make more sense to rip the guy to shreds or to respond in a civilised way?)

Duncan, does the 100A rating of the main switch/RCD mean "I can routinely carry up to 100A load current" or "I will detect an overcurrent and disconnect if I carry above 100A"? Answer almost certainly the first but it's down to you to check that. It is quite a basic distinction that you should be aware of to practice competently. Good luck with the assessment.

 

[mechelec]

Good luck with the assessment. Let us know how you get on. Don't worry about it, I bet you will get through no problem.

 

[nickblake]

as Sintra has said also so many people make the mistake in thinking that an RCD is an over current device its not its a residual current device rated at 63 , 80, 100 amps etc (main switch RCD)one thing I would say is check what the cut out is labelled as and ensure its higher , you done know what fuse is I the cut out and should not cut the seas to find out

 

[Meggerman]

Here's a scenario, I'm adding two new circuits to a mini consumer unit for my first ever NAPIT inspection... Just noticed that the main switch/RCD is rated to 100amps but the suppliers main fuse is only 80amp, should I change the RCD to one that's 80amp or lower, I don't want the NAPIT spark to think I've over looked anything...
just to add detail the circuits on the board are as follows, oven 32amp breaker! shower 45amp breaker, jacuzzi 20amp breaker.

Hi Duncan. You state mini consumer unit. Is there more than one? If so are the supply tails split to this consumer unit or is it fed from the main consumer unit?

 

[MDJ]

sad fact these days, tony, that schoolboy blunders, not knowing the difference between an isolator and a OCPD, are common occurrences with under trained , under qualified, domestic installers. only ones to blame are the scam providers for putting money before safety and the governments that let these parasites continue to operate.

Careful Tel your views although right may rile the forum Trolls here.

 

[trev]

Careful Tel your views although right may rile the forum Trolls here.

There's only one as far as I'm concerned, Biff. The officially sanctioned forum approved troll.

 

[MDJ]

This has to be a wind up. If a first year apprentice had asked me that his ears would still be ringing next Saturday.

Assessment? Do you think you are even competent?

No chance it is real, I wish it wasn't.

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There's only one as far as I'm concerned, Biff. The officially sanctioned forum approved troll.

Nope there are others fighting for his crown, at least one banned for it recently as well LMAO

 

[trev]

They can fight for his crown all they like mate, they'll lose.

 

[MDJ]

They can fight for his crown all they like mate, they'll lose.

Oh yeah for sure Trev lol

 

[NickD]

one thing I would say is check what the cut out is labelled as and ensure its higher

Just for clarity I take it you mean check that the rated current of the main switch/RCD is higher than the rating of the cutout fuse?