Roger (Moore) the Kitchen Sink?

[tricia]

Hi

Sorry for yet another question on bonding, but I have read and read thru the forums
here and still cannot find the answer I need.

I have a new steel kitchen sink and it says on it,
"This sink must have a positive earth connection"

So, do I bond this sink to the copper pipes beneath it or not?

(And it you're still reading, in my bathroom, about 15cm to the right of the bath I have
a radiator (it is steel with white paint on it plus a chrome tube at the top for hanging towels on.) It is supplied with hot water by copper water pipes connected to the rest of the CH system. Do I need to fit a copper earth bonding cable to this too?)

Thanks in advance

 

[fido]

You can't rely on the taps to earth the sink as there are probably rubber washers and plastic nuts used. You can take an earth wire from a bonded pipe to the earthing point on the sink. With the chrome towel rail I would be inclined to check earth continuity with a multimeter and only fit an earth wire if you don't read a short circuit.

 

[plugwash]

NO

what you bond are metal objects leaving the supplementry equipotential zone

there is no need to bond either the sink or the towel rail

the pipes supplying the towl rail if metal however should be bonded

supplementry bonding in the kitchen is not a regs requirement bit if you do do it then the same principle applies bond the pipes not the accessories

 

[fido]

Why do stainless steel sinks, steel baths and heated towel rails have earthing terminals on them then? I will carry on earthing them anyway as I can't see any problem with this.

 

[kendor]

Why do stainless steel sinks, steel baths and heated towel rails have earthing terminals on them then? I will carry on earthing them anyway as I can't see any problem with this.

I'm in agreement with you fido and i think this debate will go on and on.
I'm against leaving metalwork floating if there is a connection through water in this case, metalwork such as wall mounted mirrors or towel rails need not be bonded unless there is cause for concern that it may have connection to earthed apparatus say through conductive paint on the wall or some other connection, the regulation in question quoted bonding any extraneous metalwork that might introduce a hazard so i interpret that as any metalwork which doesn't have an infinity or suitably high reading for insulation to earth and therefore has a potential for creating a potential difference. As you say, Why continue to supply sinks etc with earth tags if it isn't needed anymore?
I still maintain that the word "equipotential" means all at same potential and not some of it but other bits needn't be.
If not the case then the word needs omitting from the regs as it is misleading.

 

[towman]

Unless of course there are plastic pipes carrying the water in which case you will be following this?
www.iee.org/Publish/WireRegs/Earthi... and new plastic pipework to house. Towman