Bathroom Bonding

MacSparky · May 23, 2008

So what has changed in the 17th that specifically affects the decision to not bond in the bathrooms now? Is it because bathrooms have to be on SELV or RCD/RCBO now or is it because the powers at be have just decided its no longer neccesary as long as incoming supplies are bonded...in which case what has changed as incoming was a necessity under the 16th.

Btw..nice write up jurassaic

Shakey · May 24, 2008

MacSparky said:
So what has changed in the 17th that specifically affects the decision to not bond in the bathrooms now? Is it because bathrooms have to be on SELV or RCD/RCBO now or is it because the powers at be have just decided its no longer neccesary as long as incoming supplies are bonded...in which case what has changed as incoming was a necessity under the 16th.

Btw..nice write up jurassaic

under 17th:

no supplemntary if all circuits in bathroom ona 30mA RCd (which they must be), meet their disconnection times, and extraneous conductive paths of resistance of 1667 ohms or less to MET/Protective bonding

Lets be honest there are few extraneous paths in a modern bathroom anyway because of plastic piping

Wills · May 24, 2008

Is it important that the wire isn't broken? I'm installing supp bonding in care homes at the moment, and I have been cutting the wire when installing, and connecting it all up at the points of contact eg cold pipe, rad.

Shakey · May 25, 2008

Wills said:
Is it important that the wire isn't broken? I'm installing supp bonding in care homes at the moment, and I have been cutting the wire when installing, and connecting it all up at the points of contact eg cold pipe, rad.

dont see why supp's have to be unbroken

I know it does with main bonds if you are running one cable out to gas and water, but supp's, you are not running a cable back, just connecting together extraneopus and exposed - so each bond is an entity in its own right - I can see no advantage of having an unbroken cable (and I have never heard of it)

MacSparky · May 25, 2008

Shakey said:
under 17th:

no supplemntary if all circuits in bathroom ona 30mA RCd (which they must be), meet their disconnection times, and extraneous conductive paths of resistance of 1667 ohms or less to MET/Protective bonding

Lets be honest there are few extraneous paths in a modern bathroom anyway because of plastic piping

Thanks shakey for the explanation, does this mean selv on rcd is a must also, for the cable's protection? only if using a pull switch then no cables will be in the wall (less than 50mm) so am still a little confused to why rcd is needed for bathroom selv lighting
(or maybe i'm just having an elderly moment lol)

Shakey · May 26, 2008

MacSparky said:
Thanks shakey for the explanation, does this mean selv on rcd is a must also, for the cable's protection? only if using a pull switch then no cables will be in the wall (less than 50mm) so am still a little confused to why rcd is needed for bathroom selv lighting
(or maybe i'm just having an elderly moment lol)

hey old fella

apart from the requirements for cables buried less than 5 cm, there is a requirement that all circuits in the bathrom are on an RCD