RCD req for bathroom lights, fan and shaver?

[FrankM45]

Im upgrading a bathroom that had 3 recessed downlights, shaver socket and extractor fan, all fed from lighting supply. No rcd device present.

Ive replaced all 3 lights, shaver skt and fan and added a double pole fused isolator to isolate everything in the bathroom if needed. 2 lights are in zone 2, 1 in zone 1.

I know I also need to add a 30ma RCD, but can I install it so it protects everything in there - e.g. after the isolator and before the loads?

Thanks

 

[PrenticeBoyofDerry]

Yes, you can protect the cable/equipment in the bathroom only via RCD. You must also protect any newly installed cable, that is buried in walls less than 50mm, that has no additional mechanical protection, regardless of location.
If you have not altered anything with regards to the circuit cable/routing and only swapped equipment for new, and supplementary bonding in the bathroom exists, then it would be possible to exclude the addition of RCD protection.

 

[JohnW2]

I know I also need to add a 30ma RCD, but can I install it so it protects everything in there - e.g. after the isolator and before the loads?

Yes. In fact, you could replace the isolator with an RCD if you wanted.

Although it probably a good idea to have the RCD, as you probably know, the regulation requiring RCD protection does not apply retrospectively (i.e. does not apply to 'existing' things/circuits) - so, since all you have done is replaced existing things (not installed anything new, other than the isolator), there probably is not a requirement for an RCD in terms of regulations.

Kind Regards, John
Edit: too slow again!

 

[FrankM45]

Many thanks prenticeboy & John - very helpful.

Yes I have only replaced items, in fact I took one circuit out - a mirror light that was redundant.

All wiring is existing, just tidied up with an extra junction box; the only 'new' wiring is a short run of 3 core & earth to the extractor fan - necessary as it has a timer fitted.

I see what you say about changing the isolator for the RCD but am I not supposed to include the isolator because of the fan? I decided to isolate the whole bathroom as it was easier and made more sense - I mean, who is going to be inspecting/repairing the fan in the dark?

Many thanks of you have more info or tips.

 

[JohnW2]

I see what you say about changing the isolator for the RCD but am I not supposed to include the isolator because of the fan?

If your isolator is a 2-pole one isolating everything in the bathroom, then you could use the RCD to achieve the same. The manufacturer of the fan may say that the fan should have its own isolator (3-pole, if it's a timer fan), but there is no regulatory requirement. In fact, the only real advantage of having an isolator just for the fan is that it enables one to work on / replace the fan without killing the bathroom lights - but your 'all bathroom' isolator kills everything, anyway!

Kind Regards, John

 

[deadshort]

Can you install a RCD FCU in the feed to the bathroom lighting at the existing CU ?

DS

 

[JohnW2]

Can you install a RCD FCU in the feed to the bathroom lighting at the existing CU ?

An RCD, perhaps, but what would be the point of an FCU?

Kind Regards, John

 

[deadshort]

RCD/FCU, smaller and can be installed flush into a 1g box.

DS

 

[Taylortwocities]

I'm sorry. Winston1 has decreed that you are not allowed FCUs on lighting circuits

13 amp sockets SHOULD NOT be on the lighting circuit nor should fused connection units.

The only solution is to replace the lighting MCB with an RCBO, or a complete new consumer unit

 

[stillp]

The only solution is to replace the lighting MCB with an RCBO, or a complete new consumer unit

That might apply on Winston's planet!

 

[PrenticeBoyofDerry]

I see what you say about changing the isolator for the RCD but am I not supposed to include the isolator because of the fan? I decided to isolate the whole bathroom as it was easier and made more sense - I mean, who is going to be inspecting/repairing the fan in the dark?

Ideally you have a three pole iso to isolate the fan only, the FCU/RCD would be upstream of that, so you can still have lighting on, even if fan is isolated.

 

[PrenticeBoyofDerry]

The only solution is to replace the lighting MCB with an RCBO, or a complete new consumer unit

Or move to mainland Europe, where things are so less complicated

 

[Iggifer]

I have used the RCD FCU on lighting circuits before. Obviously not a solution for every situation but next to the DB, labelled up I can't see any issue with it

Could fit a 20A BS1362 like the guy in CEF suggested we use earlier

 

[PrenticeBoyofDerry]

I have used the RCD FCU on lighting circuits before. Obviously not a solution for every situation but next to the DB, labelled up I can't see any issue with it

Done the same, when needs must and as they tend to be active, better location than the loft if you have power loss on circuit.

 

[Iggifer]

Done the same, when needs must and as they tend to be active, better location than the loft if you have power loss on circuit.

Yup, and the loft is generally an easier place to install it, but I like to think of myself as somewhat conscientious