Earth bonding

[dizwoz]

A little advice please, if all my bathroom pipes are plastic but may have some copper stems leading to taps and radiator do I still need to earth the radiator and tap stems?

 

[garythekitchenfitter]

there is no need to bond the copper stems if they are fed by plastic because there is no path to earth hope this helps but some old skool sparkys go bonding mad.
ps i,m nic eic registered as well as part p qualified oh and corgi reg

 

[dizwoz]

Gary

Many thanks for that I thought that would be the case, but can you clarify whether I need to earth the radiator as it's fixed by metal brackets to the wall?

Many thanks again

 

[TANNERS]

ALL extraneous CONDUCTIVE PARTS MUST BE BONDED TO THE MAIN EARTHING CONDUCTOR

therefore all metalwork in the bathroom should be bonded

also a strap from your copper flow or return up on to the rad is required
if you are going all out a link between light fitting and shower/shaver point to pipework wouldnt go amiss

also have you bonded your boiler ,and main gas, and water, within 300mm of the point of entry to the house, before any t's

 

[Al-Glasgow]

Quote:
also a strap from your copper flow or return up on to the rad is required .

I have never noticed these, I argued with my lecturer about this, he was unsure in the end.

Have recent regs (part p) included this on new installs ?.

Al

 

[andy]

also have you bonded your boiler ,and main gas, and water, within 300mm of the point of entry to the house, before any t's

600mm

 

[dizwoz]

Mant thanks everone, I'll bond from light switch to rad to shaver socket.

Tanners, yes there are all bonded but thanks for raising the question it made me double check.

 

[garythekitchenfitter]

No disrespect to the other guys but the reg book quotes "supplementary bonding is not required to metal parts supplied by plastic pipes, such as metal hot and cold water taps supplied from plastic pipes. A metal bath not connected to extraneous-conductive-parts (such as structural steel work). With plastic hot and cold water pipes and plastic waste pipes does not require supplementary bonding. supplementary bonding in a bathroom or shower room will still be required between the protective conductors of circuits supplying class 1 and class 2 equipment in the zones eg. heaters showers and accessible luminaires."

 

[TANNERS]

the way i look at it,is if a potential was raised on say the hot tap , it would be live , yes

you touch it create a circuit

if it is bonded the current would flow through the bonding straps/earth cable to earth causing the overcurrent device would operate eliminating the potential

does that make sense

SORRY 600MM WE DO 300 CAUSE THE CLAMP IS hidden IN THE METER BOX

 

[Spark123]

No disrespect to the other guys but the reg book quotes "supplementary bonding is not required to metal parts supplied by plastic pipes, such as metal hot and cold water taps supplied from plastic pipes. A metal bath not connected to extraneous-conductive-parts (such as structural steel work). With plastic hot and cold water pipes and plastic waste pipes does not require supplementary bonding. supplementary bonding in a bathroom or shower room will still be required between the protective conductors of circuits supplying class 1 and class 2 equipment in the zones eg. heaters showers and accessible luminaires."

Yes, 100% correct

 

[garythekitchenfitter]

i understand what u r sayin but if it is connected by plastic nothing can pass through it .

 

[Spark123]

I think this may have been better posted in electrics UK,

ALL extraneous CONDUCTIVE PARTS MUST BE BONDED TO THE MAIN EARTHING CONDUCTOR

Yes, at the point of entry to the building utilising main equipotential bonding conductors in a metal piped system. Not much point bonding to plastic pipes though.

therefore all metalwork in the bathroom should be bonded

Only if it is extraneous or exposed conductive parts. This bonding is local to the bathroom and not not required to go back to the MET.
If items are fed by plastic pipes then they are unlikely to be either and hence these items do not require supplementary bonding.

the way i look at it,is if a potential was raised on say the hot tap , it would be live , yes

you touch it create a circuit

How can a tap fed from plastic pipework introduce a potential?

if it is bonded the current would flow through the bonding straps/earth cable to earth causing the overcurrent device would operate eliminating the potential

No, equipotential bonding is about reinforcing the equipotential zone within the bathroom hence everything within will be at (or very close to) the same potential reducing the electric shock risk. (i.e. Faraday cage.)

 

[dizwoz]

Thank you again everybody, however I've now run the cable from the earth in the light switch to the radiator stems and then on to the shaver socket earth, so I assume thats belt and braces or am I creating any additional problem?

 

[Spark123]

As you say the c/h pipework is plastic with short copper stems to the radiator then it isn't likely to introduce a potential into the room and hence will not require bonding. (unless it is in contact with something else such as a metal building support.)

 

[TANNERS]

theres your answer then m8

don't do any additional work thats not required by regs no matter how safe

i would do it and i would take a link to
other pipework. so that every exposed metal part is at the same potential

but don't buy more cable if youve run because as the guys said its not requierd

and this is not in electrics uk because it started as advice on a home project