Consumer Unit - Earth Leakage Circuit Breaker

[jonelv]

Hello

About to build an extension and looking at new ring main to feed new kitchen / utility room. Cooker on separate dedicated of course. My consumer unit has space and capacity for a new MCB but I note that the main switch is a 30mA trip current earth leakage circuit breaker. As the operation of an ELCB is different to an RCD, will I need a 30mA RCBO for my new ring main in order to comply with 17th Edition Regs. I don't really want to upgrade whole unit as works fine, trips when necessary e.g. kettle / toaster knackered - without excessive nuisance trips. Any thoughts? Thanks

 

[ericmark]

An ELCB-c is a RCD there were years ago ELCB-v but these have been outlawed for many years.

So unless you used a 10ma RCD it would be pointless.

However who ever is going to issue the completion certificate will advise you on this anyway.

Where a single RCD is included in a consumer unit they are often of the split type and you may need a RCBO if supplied from non protected side.

 

[Adam_151]

As eric says, a current operated ELCB (which is what you have if it has a rating in mA on the side) is the old name for an RCD and as long as it tests out ok, there is no issue with that.

Its the voltage opperated ELCBs that are no longer recognised by the regs due to the fact that modern bonding requirements can render them ineffective

 

[rebuke]

The problem you may have however is the 17th edition of the regs does not allow all circuits to be protected by one RCD, due to the inconvenience if it trips. While you're not obliged to change your existing set up, your new circuits shouldn't be added to it as is, so an electrician may need to either replace your current CU, or at least put in a mini one for your new circuits...

If you're doing it yourself, then you will probably also need to comply with this, or the LABC are unlikely to sign off on the electrical work (new circuits are notifiable under Part P of the building regs).