can a consumer unit switch be replaced by an RCD?

[alanma]

HI
My flat just failed the EICR because there is no RCD in the consumer unit.
There is no space for a new RCD as the consumer unit is full.
Do I have to have a new larger consumer unit installed?
Or can I have the existing on/off switch replaced by an RCD?

Thanks
Alan

 

[brianmoooore]

If a RCD that would fit were available (unlikely),it would solve the lack of RCD problem, but you'd then fall foul of a different regulation regarding selectivity.

 

[alanma]

Hi Brian thanks for responding, can you tell me what selectivity is in this con
text?
Many thanks
Alan

 

[DPG]

Hi Brian thanks for responding, can you tell me what selectivity is in this con
text?
Many thanks
Alan

If you have one RCD covering the whole installation then any earth fault will result in loss of power (including lighting and fridge) to the whole house.

Also, all circuits naturally have some amount of earth leakage. If all circuits are fed from one RCD then this total leakage figure may be enough to trip the RCD, even though there is no actual fault.

 

[alanma]

If you have one RCD covering the whole installation then any earth fault will result in loss of power (including lighting and fridge) to the whole house.

Also, all circuits naturally have some amount of earth leakage. If all circuits are fed from one RCD then this total leakage figure may be enough to trip the RCD, even though there is no actual fault.

Thanks again, This is just a one bedroom flat, I understood that a single RCD is allowable according to regulations, is that not correct?
Many thanks

Alan

 

[DPG]

Thanks again, This is just a one bedroom flat, I understood that a single RCD is allowable according to regulations, is that not correct?
Many thanks

Alan

How many circuits are there?
Photo of consumer unit would be useful as well if you have one.

 

[alanma]

Hi, there are 5 circuits and a switch

 

[DPG]

RCBOs would be an ideal upgrade without excesivs cost. This gives individual RCD protection to each circuit. The main switch would remain as-is.

 

[alanma]

Thats something I had not considered.
So each of the 5 fuses would be replaced by a single width RCBO is that right?
How much would the RCBOs cost?
Would that pass an EICR?
Thanks
Alan

 

[westward10]

You won't get RCBOs for that board. Being cynical here but the amount of undisturbed dust on the conductors and mcb switch toggles did they actually do anything in the consumer unit. If you redact any personal info seeing the EICR could be interesting.

 

[DPG]

You won't get RCBOs for that board. Being cynical here but the amount of undisturbed dust on the conductors and mcb switch toggles did they actually do anything in the consumer unit. If you redact any personal info seeing the EICR could be interesting.

Fair point.

 

[alanma]

Hi

You won't get RCBOs for that board. Being cynical here but the amount of undisturbed dust on the conductors and mcb switch toggles did they actually do anything in the consumer unit. If you redact any personal info seeing the EICR could be interesting.

Hi, can you tell me why I won't get RCBO's, is the board too old?
BTW its an old photo, was shot during some maintainance years ago
Here is the EICR for your perusal

 

[westward10]

All the circuits are listed as unknown and multiple tests are just LIM but with no reasoning. They say they didn't access the service head but have identified the earthing system as TN- S.

 

[alanma]

All the circuits are listed as unknown and multiple tests are just LIM but with no reasoning. They say they didn't access the service head but have identified the earthing system as TN- S.

Sorry I don't know what that means, can you tell me?
Thanks
Alan

 

[westward10]

How long were they there for.
The earthing system can generally only be verified by accessing the service head, they say they didn't access it.