cooker tt no rcd

midgetman · Dec 9, 2014

hi extended a 32 amp cooker circuit, adding a cooker switch and outlet plate. extended as it is a 7kw range cooker now situated in fireplace. old cooker now not going to be used.

problem is its on a 16th edition board and is on tt. the cooker and lighting are non rcd protected.

ideal would be to either go on rcbo or add another rcd.

how ever customer does not want to spend so can the cooker go on the 63amp rcd. there is no shower and only the rings on it.

as I said not ideal but got to be safer.

if above would then be notifiable and not minor works?

thanks

Pete999 · Dec 9, 2014

What with no OCPD?

SirKit Breaker · Dec 9, 2014

midgetman said:
as I said not ideal but got to be safer.

thanks

But not safe! It is your name going on it, and you maybe doing him a favour saving him a few quid, but that will all be forgotten when someone gets hurt, and then guess where the finger will point.

Cheers...............Howard

midgetman · Dec 9, 2014

cooker is on 32 amp mcb.

midgetman · Dec 9, 2014

oops wrong pic

Pete999 · Dec 9, 2014

SirKit Breaker said:
But not safe! It is your name going on it, and you maybe doing him a favour saving him a few quid, but that will all be forgotten when someone gets hurt, and then guess where the finger will point.

Cheers...............Howard

Not safe with no over current protection? jeez

telectrix · Dec 9, 2014

hang on. the cooker does not, nor has ever , required RCD protection. if the cable feeding the cooker isolator is buried<2" deep in wall/s, then that cable may need RCD.

midgetman · Dec 9, 2014

cable is surface mounted. (fixed to wall securely behind kitchen units) however I thought all tt had to be now rcd protected..

telectrix · Dec 9, 2014

you fit RCDs to a TT system if the Ze is too high to give acceptable Zs readings. a decent TT system with sub 1 ohm Ze may well negate the need for a RCD.

midgetman · Dec 9, 2014

yeah well it's Ze is 121

midgetman · Dec 9, 2014

I can't see it being unsafe by putting on to the rcd side. inconvenient in case of fault but not unsafe.

maybe I see if I can find rcbo.. cheers

telectrix · Dec 9, 2014

no problem with doing that, midget. better safe than sorry.

BES · Dec 9, 2014

Am I missing something here. There's a spare way on the rcd side of the board so either move cooker over or get an rcbo. Issue mwc for extending circuit get paid run away

ferg · Dec 9, 2014

BES said:
Am I missing something here. There's a spare way on the rcd side of the board so either move cooker over or get an rcbo. Issue mwc for extending circuit get paid run away

If you are then I am as well TBH.

midgetman · Dec 9, 2014

well that was wit I was querying from the start lol... run away? haha

BES · Dec 9, 2014

midgetman said:
well that was wit I was querying from the start lol... run away? haha

I think the problem was the way you worded you first post suggested you were going to wire cooker circuit directly from the 63a rcd. Got some of the oldies a bit excited

midgetman · Dec 9, 2014

ohh sorry my fault..

BES · Dec 9, 2014

midgetman said:
ohh sorry my fault..

Some brilliant sparks on here who really know there stuff but they get a bit wound up now and again

midgetman · Dec 9, 2014

there's enough spare ways to put lights on rcd as well. Thought 16th you had to have upfront rcd on board..

davesparks · Dec 9, 2014

What type of RCBO were you thinking of fitting to this board?

TJ Anderson · Dec 9, 2014

You wont overload that RCD in a house with the just the RFC's and cooker on it. Just move it over to RCD side if it is even required for your installation method (buried cabling?). No need for RCBO. Don't put lights on same RCD though, leave it alone unless you have worked on circuit and RCD protection is now required, then RCBO it to minimise disruption under single circuit fault condition.

midgetman · Dec 10, 2014

davesparks said:
What type of RCBO were you thinking of fitting to this board?

dp if possible. if not fit new rcd which is dp and then in effect making it a twin rcd board.

Engineer54 · Dec 10, 2014

midgetman said:
dp if possible. if not fit new rcd which is dp and then in effect making it a twin rcd board.

It's going to be difficult to install a DP or SP+N RCBO in a standard CU unless are stand alone. Far better to go the dual RCD route.

Actually with TT CU's and DB's all protective devices should be DP, not that many if any take any notice, or even if they know why!! lol!!

Octopus · Dec 10, 2014

midgetman said:
there's enough spare ways to put lights on rcd as well. Thought 16th you had to have upfront rcd on board..

I wouldn't do that. Leave the lights on the non RCD side so when the RCD trips, the lights stay on.

You work is related to the cooker circuit, NOT the whole installation.

The MWC comments section should be used appropriately!

Pete999 · Dec 10, 2014

BES said:
I think the problem was the way you worded you first post suggested you were going to wire cooker circuit directly from the 63a rcd. Got some of the oldies a bit excited

OIY you pack it in lol

amckay · Dec 10, 2014

I agree with Murdoch's comment above.

Kate · Dec 10, 2014

Shouldnt 16th edition cu's on TT have 100ma rcd up front?

Deleted member 26818 · Dec 11, 2014

Kate said:
Shouldnt 16th edition cu's on TT have 100ma rcd up front?

All circuits will require fault protection which is usually provided by one or more RCDs.
I would have expected an S type 100mA RCD up front, and 30mA RCD protecting the downstairs sockets.
As it is, the OP will have to ensure that the new cooker circuit is provided with 30mA RCD protection.
This can be achieved by using a spare way on the RCD side of the board, or by using an RCBO on the non RCD side of the board.
The OP will then be left with either persuading the customer into having the MCBs on the non RCD side replaced with RCBOs, or just commenting on the lack of RCD protection on the EIC.