Secondary ccu

[Davem]

Hi just fitting a secondary ccu to some kennels ad was just think that the secondary board main switch is 60 amps and the breaker supplying from the main board is 40 amp so if there was a problem the main board breaker would trip before the kennel one how do I combat this. New to the game guys please be nice x

 

[Plonker 3]

The clue is in the name "switch" that's all it is not a OCPD. So nothing to worry about.

 

[Davem]

Ok thank you I thought I could have two stand alone ccu so if there was a problem with kennel ccu it wouldn't trip in the house ??

 

[GLENNSPARK]

go get an electrician in...
caus you certainly aint...

 

[Davem]

Thanks for help mate appreciate help

 

[Hiddo]

Dear O Dear

 

[Richard Burns]

So long as your breakers in the secondary CU are less than 20A then you should have discrimination from the 40A supply breaker, but please do learn what you are installing and what they do, it is very important.

 

[johnboy6083]

So long as your breakers in the secondary CU are less than 20A then you should have discrimination from the 40A supply breaker, but please do learn what you are installing and what they do, it is very important.

You will only have overload discrimination.
As a general rule, MCBs will not offer full discrimination with another MCB, that is overload and short circuit.