RCD on cooker circuit ??

[Dazza1976]

Hi all,

Just wanted to hear your views on this one, as im in the process of re-wiring my kitchen.
I have completed my City and Guilds in electrical installation parts 1+2, and my tutor who had 30 years experience in the trade, said you should not put the cooker circuit on an Rcd because it causes nuisance tripping due to earth leakage.
However other bits of info i have read over the months have said otherwise, and that you should always have it on an Rcd.
I will be interested to hear your opinions on this one.

Thx.

 

[vardymr2]

If the cooker point has a socket outlet i always but it on a RCD, However if you are pulling in a new circuit for the cooker it should be done to 17th which really means it should be RCD protected anyway

 

[stevie h]

your tutor is right it can cause nuisance tripping but as mentioned, under the 17Th basically everything has to be on an RCD unless the cables are enclosed in earthed conduit / capping

 

[Spudmiester]

My whole house is on an RCD and it rarely trips at all.

 

[spark-doctor]

What your tutor may of meant was not to put the cooker on a bank of mcb's protected by a RCD but put it on a non RCD protected way with a RCBO.

Reading that, i have confused myself

 

[Carter]

your tutor is right it can cause nuisance tripping but as mentioned, under the 17Th basically everything has to be on an RCD unless the cables are enclosed in earthed conduit / capping

Not necessarily, provision exists for dispensing with RCDs in specific circumstances. eg 314.1 (iv) designated/marked circuits etc but if the cooker point has a socket then no matter whether it's suitably marked there is nothing stopping Joe Public running an extension lead through the kitchen window to the cooker socket therefore the requirement for additional protection (reg 415.1) has to take priority.
If diagnosing a cooker that's tripping an RCD it's an idea to get an idea of the appliance's PEAK leakage current in its cold condition as it will be at switch on from cold when the cct. resistances are at their lowest so will allow the maximum leakage currents to flow. As it heats up they will lessen. If there's no fault with the wiring and the tripping is confirmed as excess leakage from the appliance you swap the skt. equipped cooker control for a simple DP switch and transfer to non-RCD protected side.