bathrooms rcd

[s.keech]

Hi can some one help. Just starting out and have passed level 3 guilds have been asked to fit a fan and downights in a bathroom. I know it is notifiable but can any one tell me how to r.c.d everything. Is the cheapest way to fit r.c.d fused connection unit outside bathroom or do i have to run new circuit from c.u. If i can use R.c.d outside bathroom do ileave the 13 amp fuse in it or change it.
Cheers for any help
Steve

 

[nickblake]

depends on what board you have old rewireable Split load dual RCD etc etc you wouldnt use a 13amp fuse on fans or lights it would be a 3 amp , and bonding must be installed to incomming services water gas oil etc its not just adding a few lights some more information would be good ,IE board type fuses or mcb's with RCD protection then i may be able to help further

 

[Deleted member 26818]

The Regulations require that the circuit be protected.
That means the whole circuit, not just a part of it.
As such the RCD protection would have to be at or very near to the origin of the circuit which is at the DB/CU.
It has also recently come to my attention, that the manufacturer's do not consider RCD FCUs as being suitable for fixed wiring.

 

[s.keech]

so that would mean running a new circuit just for the bathroom then. is there not an easier way

 

[s.keech]

I will know more when i see it and give more info

 

[nickblake]

No not at all RCD the whole circuit seperate board with an RCD on it , but like i have said what is the current protection , fuses mcb's etc

 

[Octopus]

The Regulations require that the circuit be protected.
That means the whole circuit, not just a part of it.
As such the RCD protection would have to be at or very near to the origin of the circuit which is at the DB/CU.
It has also recently come to my attention, that the manufacturer's do not consider RCD FCUs as being suitable for fixed wiring.

Spin, out of interest why do the RCD FCU's get sold then?

I have to admit to using RCD FCU's - there are times when its the only way to get near to the regs.

 

[s.keech]

do r.c.d sockets not just protect what is plugged into them

 

[Octopus]

do r.c.d sockets not just protect what is plugged into them

Yes, correct.

 

[smu_diddly]

You do not have to rcd the whole circuit, just the part you are altering and anything down river from it. My niceic inspector confirmed that for me. I always use this method when the cu is too old for a rcbo and the customer too tight to have the cu changed

 

[HandySparks]

It has also recently come to my attention, that the manufacturer's do not consider RCD FCUs as being suitable for fixed wiring.

Got a reference for this, spin?

 

[smu_diddly]

??? Plug in or fixed what difference would it make?!!

 

[Deleted member 26818]

Spin, out of interest why do the RCD FCU's get sold then?

I have to admit to using RCD FCU's - there are times when its the only way to get near to the regs.

Not really sure.
Yes Handysparks, here's a link to the Beama RCD handbook: RCD Handbook updated - BEAMA | News.
There's a little chart on page 26.

 

[SPARTYKUS]

The Regulations require that the circuit be protected.
That means the whole circuit, not just a part of it.
As such the RCD protection would have to be at or very near to the origin of the circuit which is at the DB/CU.
It has also recently come to my attention, that the manufacturer's do not consider RCD FCUs as being suitable for fixed wiring.

He not installing the whole circuit, just adding to it....? I'd be interested to see the black & white on that one, in this case common sense ( my common sense) is telling me that protecting the addition with a 30mA Rcd means, well, what I have done, is protected. And not some cobblers someone else may well have done and Im not being paid to look into?

 

[Deleted member 26818]

Spartykus.
Do you agree that the Regulations require RCD protection for circuits of locations containing baths and showers?
If not, no worries.
If you do, can you explain how only protecting part of the circuit complies?

Something else, that it appears many are not aware of.
Is that if only part of the circuit is protected, then current from an earth fault on the unprotected part of the circuit will by pass the RCD and enter the location.

 

[Octopus]

Not really sure.
Yes Handysparks, here's a link to the Beama RCD handbook: RCD Handbook updated - BEAMA | News.
There's a little chart on page 26.

Call me cynical but the members are principally manufacturers who would prefer you to buy more expensive kit like consumer units.

(P26 table)

 

[SPARTYKUS]

Not really sure.
Yes Handysparks, here's a link to the Beama RCD handbook: RCD Handbook updated - BEAMA | News.
There's a little chart on page 26.

Great guide link there Spin thank you. Some lovely equations at the back

 

[Octopus]

Spartykus.
Do you agree that the Regulations require RCD protection for circuits of locations containing baths and showers?
If not, no worries.
If you do, can you explain how only protecting part of the circuit complies?

Something else, that it appears many are not aware of.
Is that if only part of the circuit is protected, then current from an earth fault on the unprotected part of the circuit will by pass the RCD and enter the location.

A point has been made before BUT I'd say that adding a RCD FCU is better than no protection, and also it can help when complying with fan manufacturers requirements to fuse down to 3A.

 

[SPARTYKUS]

Spartykus.
Do you agree that the Regulations require RCD protection for circuits of locations containing baths and showers?
If not, no worries.
If you do, can you explain how only protecting part of the circuit complies?

Something else, that it appears many are not aware of.
Is that if only part of the circuit is protected, then current from an earth fault on the unprotected part of the circuit will by pass the RCD and enter the location.

Hmm.

I don't disagree with you, but...!

 

[Deleted member 26818]

I guess at the end of the day, it's down to the individual to make their own choice.
I would not be able to justify installing an RCD in such a manner that it did not offer as much protection as possible.

 

[smu_diddly]

Spartykus.
Something else, that it appears many are not aware of.
Is that if only part of the circuit is protected, then current from an earth fault on the unprotected part of the circuit will by pass the RCD and enter the location.

If the earthing is correct it will not. if done right it will flow down the cpc to the db earth and cause the the mcb or fuse to operate. as the unprotected side will be before the rcd. i cant imagine it going the other way unless the impedance is too great and a earth path exists in the bathroom with a lower impedance.

 

[s.keech]

would that maen r.c.d ing the whole upstairs lighting where the bathroom is

 

[smu_diddly]

if you can great, its covers all areas, just watch for borrowed neutrals if using rcbos.

 

[Deleted member 26818]

If the earthing is correct it will not. if done right it will flow down the cpc to the db earth and cause the the mcb or fuse to operate. as the unprotected side will be before the rcd. i cant imagine it going the other way unless the impedance is too great and a earth path exists in the bathroom with a lower impedance.

The current will take any available path, not only will it flow back to the origin of the installation, it will also enter the location.
Yes hopefully the OCPD will operate within the specified time of 0.4s.
However the Regulations now require the use of a protective device with an operation time of 0.04s, specifically an RCD.

 

[HandySparks]

Not really sure.
Yes Handysparks, here's a link to the Beama RCD handbook: RCD Handbook updated - BEAMA | News.
There's a little chart on page 26.

Thanks, spin.
Interesting chart. You're right, it does show that a FCURCD is not recommended for protecting fixed wiring. However is also says that it IS suitable as an outgoing device on a CU or DB and that it IS suitable for protecting socket outlets of 20A or less. About the same level of ambiguity as the wiring regs then!

 

[DNS1]

I remember having a long discussion with my college tutor (former ECA inspector) about RCDs in bathrooms.

I had always been of the understanding that I only have to RCD protect the circuit being worked on (ie: if installing a shower, protect the shower radial and go home) but he told me that I'd have to make sure the lighting circuit (at least the bathroom section of it) was RCD protected too.

I will never understand exactly why...

 

[Deleted member 26818]

People think my interpretation is over the top.
I think that that particular misunderstanding is due to the wording 'all low voltage circuits of the location'.
Some interpret that to mean, that if you work on one circuit, not only must you provide RCD protection for that circuit, but for all.

 

[rich.250]

I agree with spin, circuits should be protected at the origin. It's that simple.

 

[SPARTYKUS]

Ok.

However.

In the real world, I know many will continue to protect, for example, the bathroom fan (in line) in the loft that supplies the bathroom with an RCD spur as a cheaper solution, based on real life cost pressures. Note Im not pushing it as right or good; neither am I saying it is wrong. Simply that I believe many will see it as a solution that makes a home safer.

The other point being whats installed is protected by an RCD. If something went wrong i'd be suprised if there was any comeback on the contractor concerned. Given the example above.


This point has been covered in many threads- the idea of leaving an install better than when one arrived.

In way of placation & to avoid being beaten senseless in electrician forum cyberspace(!) i do agree however that simply protecting the whole circuit at source is the best idea. In theory! In practise it may turn a £120 job into a much bigger, moretime consuming, and therefore unacceptable-to-the-client job!!

 

[sedgy34]

Rcd spur in the loft protecting the bathroom (new circuit from distribution board for bathroom :smilielol5:you having a laugh!!!

 

[Octopus]

Rcd spur in the loft protecting the bathroom (new circuit from distribution board for bathroom :smilielol5:you having a laugh!!!

Why put it in the loft, place it outside on the wall high up and that way it can double up as the fan 3A fuse and isolation switch for the fan!

 

[SPARTYKUS]

Call me cynical but the members are principally manufacturers who would prefer you to buy more expensive kit like consumer units.

(P26 table)

You cynic!!

 

[morph]

common sense applies
rcd the whole circuit is best
rcd the stuff you work on is sufficient

 

[sedgy34]

Why put it in the loft, place it outside on the wall high up and that way it can double up as the fan 3A fuse and isolation switch for the fan!

just out the way and not in view to look at everytime the customer crawls them stairs!

 

[SPARTYKUS]

just out the way and not in view to look at everytime the customer crawls them stairs!

need one with a little LED then, at least, and flashing :biggrin5:

 

[sedgy34]

need one with a little LED then, at least, and flashing :biggrin5:

you still sulking cause i was in your area lol :ciappa: