Just been delving deep under the new unit in the bathroom for the first time following my re-fit plus electric shower install last summer. I notice that there is one of those earth clamps joining the hot and cold pipes going to the sink. I can't see where this earth wire leads as there's no extra wire coming down to the CU in the pantry. So where will the spark have wired it into the earthing system?
Bathroom electrics
- Thread starter Vicario
- Start date
What you see there is supplementary equipotential bonding, not earthing. Earthing and bonding are not the same, and supplementary bonding cables are not taken back to the CU.
They should be connected to the earth conductors of circuits supplying things in the bathroom, but it's possible that that was done elsewhere - can you see any cables on pipes under the bath/in the airing cupboard/under the floor/in the loft?
They should be connected to the earth conductors of circuits supplying things in the bathroom, but it's possible that that was done elsewhere - can you see any cables on pipes under the bath/in the airing cupboard/under the floor/in the loft?
It's probably supplementary bonding, which should link all exposed metalwork (i.e. pipes, radiators etc), and the CPCs of any electrical circuits in the room. It doesn't go back to the CU / MET (Main Earth Terminal).
Under the 17th edition, if all circuits in the room are are RCD protected, and a couple of other conditions are met, then supplementary bonding can be omitted.
When you fitted the shower, did you join the CPC of that circuit in to the supplementary bonding, if not, then are all circuits RCD protected?
Under the 17th edition, if all circuits in the room are are RCD protected, and a couple of other conditions are met, then supplementary bonding can be omitted.
When you fitted the shower, did you join the CPC of that circuit in to the supplementary bonding, if not, then are all circuits RCD protected?
It was fitted by a professional. He fitted a separate 63A CU with 50A MCB and separate RCD for the shower. It is cabled in 10mm. There's a 45A pull switch on the bathroom ceiling to isolate the shower. The only other electricity in the bathroom are the lights (from a 5A breaker in the main CU). These are pull-switch operated too.
I'm losing track of what year it is - none of the above information on supplementary bonding may be relevant - when last year was it done?
Are all the bathroom circuits RCD protected?
Is your main bonding in place?
What version of BS 7671 does the EIC mention?
What does it say about tests of bonding?
July
Bathroom lights not on RCD
Off for the weekend now - will check the cert. next week, although he did take up the floorboards and run a new wire from the kitchen main clamp to the CU and used lots of meters! Didn't see him touch the one at the gas meter though.
Bathroom lights not on RCD
Off for the weekend now - will check the cert. next week, although he did take up the floorboards and run a new wire from the kitchen main clamp to the CU and used lots of meters! Didn't see him touch the one at the gas meter though.
Then that circuit should be connected to the supplementary equipotential bonding, as should the shower one, RCD or no.
Can you see any cables on pipes under the bath/in the airing cupboard/under the floor/in the loft?
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