consumer unit RCD

[madstu]

Just had a new consumer unit fitted it has 5 MCB and 1 RCD the electrician said it is 17th edition but someone has told me it should have 2 RCDs and the MCB should be split between them who is right.

 

[PrenticeBoyofDerry]

No, one RCD is permitted, two would be nice though!
If you had two, it would prevent all the electric going off, when one or the other RCD trips, as you can split the circuits.
But One RCD is not breaking any requirement.

 

[xr4x4]

I thought the main difference between 16th and 17th was making allowances for not allowing total power cuts?

Hence dual rcd.

Guess I'm wrong!

Edit

In 17th came the requirement for all circuits to be protected by a rcd.

 

[PrenticeBoyofDerry]

There is no specific Reg stating that you can’t fit a consumer unit with only one main RCD

 

[JohnW2]

There is no specific Reg stating that you can’t fit a consumer unit with only one main RCD

True, but 314 implies that one should not have all final circuits run off one RCD.

Kind Regards, John.

 

[Taylortwocities]

Just had a new consumer unit fitted it has 5 MCB and 1 RCD the electrician said it is 17th edition but someone has told me it should have 2 RCDs and the MCB should be split between them who is right.

Can we see a picture of your consumer unit, please?

 

[westie101]

should not

Rather than must not! Should is classed as advisory not mandatory (if anything can be mandatory in a set of guidelines)

 

[madstu]

Just had a new consumer unit fitted it has 5 MCB and 1 RCD the electrician said it is 17th edition but someone has told me it should have 2 RCDs and the MCB should be split between them who is right.

Can we see a picture of your consumer unit, please?

From left to right
RCCB 80A,shower,cooker,sockets,lights,boiler,main switch

 

[JohnW2]

should not

Rather than must not! Should is classed as advisory not mandatory (if anything can be mandatory in a set of guidelines)

Yes, that's the usual convention in such documents. However, the 'should' word was mine, the actual word in 314.1 of the regs being 'shall':

314.1 Every installation shall be divided into circuits, as necessary, to:
(i) avoid hazards and minimize inconvenience in the event of a fault
... (iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit.....

It's obviously all a bit vague. In most fiedls I work in, 'shall' is close to the 'must' end of the 'may....should....must' spectrum - although, in the absence of definitions (and particularly given that BS7671 is not mandatory in the first place), there is clearly scope for varying interpretations.

Kind Regards, John

 

[Taylortwocities]

Just had a new consumer unit fitted it has 5 MCB and 1 RCD the electrician said it is 17th edition but someone has told me it should have 2 RCDs and the MCB should be split between them who is right.

Can we see a picture of your consumer unit, please?

From left to right
RCCB 80A,shower,cooker,sockets,lights,boiler,main switch

That APPEARS to be a split load consumer unit. I would need to see a picture with the cover off.
I am assuming that the wiring for your boiler and lighting are buried in the walls (ie not surface wiring?)
If so that consumer unit does not appear to comply with 17th edition of the wiring regulations. But lets have a look inside before we fire the starting gun.

 

[madstu]

This is a link to item
http://www.qvsdirect.com/Excel-10-W...-Mainswitch-80A-30mA-RCD-6-MCBs-pr-22630.html

All the cables are in the wall

 

[Taylortwocities]

In that case you have been diddled and the electrician has lied to you.

To comply with 17th edition, all circuits must be RCD protected. This is required if wiring is concealed less than 50mm from the surface (yours will be).

The two circuits on the right next to the main switch have no RCD protection.
The MCBs should be removed and changed for RCBOs or he needs to install a board that DOES comply. One of these http://www.qvsdirect.com/Excel-12-W...ainswitch-RCDs-MCBs-Split-5-5-2-pr-23773.html if you must have cheapo Excel stuff.

Was the electrician registered with any of the Part P schemes? Find out and complain very loudly.

You should have had an installation certificate for the change of the consumer unit. Also a Building regulations Completion Certificate.

These will occur because the electrician will have declared that the work he has done complies with BS7671 and Building Regulations Part P. But he hasn't so that is a lie and fraud.

 

[bernardgreen]

Who told you about QVS and who actually bought the CU from QVS. the electrician or you yourself.

Did you by any chance happen to be the electrician who fitted it ?.

 

[xr4x4]

In that case you have been diddled and the electrician has lied to you.

To comply with 17th edition, all circuits must be RCD protected. This is required if wiring is concealed less than 50mm from the surface (yours will be).

The two circuits on the right next to the main switch have no RCD protection.
The MCBs should be removed and changed for RCBOs or he needs to install a board that DOES comply. One of these http://www.qvsdirect.com/Excel-12-W...ainswitch-RCDs-MCBs-Split-5-5-2-pr-23773.html if you must have cheapo Excel stuff.

Was the electrician registered with any of the Part P schemes? Find out and complain very loudly.

You should have had an installation certificate for the change of the consumer unit. Also a Building regulations Completion Certificate.

These will occur because the electrician will have declared that the work he has done complies with BS7671 and Building Regulations Part P. But he hasn't so that is a lie and fraud.

Ok, so there's a gap in the mcbs, but that doesnt mean all the circuits aren't rcd protected.

Bit odd I admit but not conclusive.

 

[JohnW2]

[Ok, so there's a gap in the mcbs, but that doesnt mean all the circuits aren't rcd protected. Bit odd I admit but not conclusive.

I agree that the appearance isn't conclusive, but the product description in the link provided by the OP is:

•6 Usable Ways: 3 MCBs on the Mainswitch + 3 MCBs on the RCCD

Kind Regards, John.