Protection for garage

[jaguar1]

Is it ok to use a single pole rcbo to protect the garage supply cable as a rcbo is a combined rcd and mcb, i was concerned that i thought both the phase and neutral conductors had to be switched off in the event of a fault or overload.

The Local electricity board replaced my dads 32a breaker (for the downstairs sockets) with an rcd now i thought a rcd only gave fault protection but not overload protection so have they made a mistake as the 32a mcb has now been removed.

 

[Spark123]

What is the reason for RCD protecting the cable to the garage? Is the garage detached?
In a detached building you should have some sort of isolator to switch off all live conductors i.e. phase and neutral.
An RCD (RCCB) does not provide overcurrent protection, an RCBO does provide overcurrent protection.

 

[jaguar1]

Hello spark123,

I wanted to protect the cable going from the house to the garage where a 2 way consumer unit will be fitted with one 6 A breaker and one 16 A breaker . I know if i have a fault on the lawnmower i will have to go to the house to reset i don't mind that .This way eveything outside the house including the supply cable to the garage is protected. I thought you had to have a means of disconnecting the garage but a rcbo if turned off will only switch the phase conductor.

 

[jaguar1]

Sorry the garage is detatched.

 

[Spark123]

The problem with your setup is that if you have a fault on a socket in the garage you will lose the lights. Might not be nice if you are using a circular saw or something at night!
Is the cable armoured? What is your supply type i.e. TN-S, TN-CS or TT?
If it is TN with an armoured cable there is no need to RCD protect it.
In the garage CU there should be an isolator switch which cuts both phase and neutral.

 

[jaguar1]

yes the consumer has a double pole switch on the main switch , but my question was can i use a rcbo for both types of protection if i install it in the house consumer unit as its a single pole ( I suppose it must be ok as you can use them for downstair sockets )

 

[Spark123]

You can use it but it isn't a good design for the reason I stated above.

 

[jaguar1]

Thanks for your reply any views on the other query i had where the electric board replaced my dads 32A breaker for a rcd is this correct as now he has no over current protection or am i missng something ??

 

[Spark123]

If it is an RCCB then there is no overcurrent protection and is wrong.
If it is an RCBO then it is fine.
Can you post a piccy of the setup?

 

[jaguar1]

i will try and get a pic later i am at work at the moment but it takes up 2 ways in the board, thanks

 

[Spark123]

Some RCBOs take up 2 ways, it may even be double pole

 

[jaguar1]

Many thanks i will try tomorrow for a pic if i get time as i am working nights !!!!