RCD test - 2 RCD's in sequence

[DoBBY]

I have a garage install protected by a 30mA rcd and a 32A breaker at main DB in dwelling, I then have a new CU in garage which also has a 30mA rcd protecting sockets and lights.

When I do the RCD test I am getting bad results. When I do the 1 x the RCD in the garage CU is not tripping but the RCD at the original DB is...what the hell is going on..?

I can't put the circuit on the main switch side of the DB because there is no room so it has to stay on the RCD side....

Any ideas?

 

[sparkdog]

No discrimination with two 30ma RCDs in series.Don't really need one in the garage if its fed from the one in the house.

 

[ezzzekiel]

as said running two rcd is pointless and the most sensitive will trip first, either remove the rcd from garage or move the circuit to a unprotected way in house (depending on wether the distribution cable requires rcd protection)

 

[tony mc]

Take the RCD out of the garage and replace it for a double pole isolator main switch on the garage board.

 

[Martin Bradley]

Did you not read my last post, to your other question ?. check it out it explains all you have to do.
your last post about EIC forms

 

[tony mc]

Sorry Martin I must have missed something.!

Had a look a yes see what you mean.!

 

[AlanWirral]

Yep as said, as long as the House RCD trips in time there's no need for another in series.