few questions

J.C.E · Feb 16, 2013

This is regarding my house (well my parents house)

where the mains water stop cock is the pipe is plastic. however the water pipes by the boiler, under rads, and in the water tank cupboard there are copper pipes

do I need main bonding or would cross bonding in 4mm at the boiler and the water tank cupboard (all pipes)

the gas is bonded with 10mm (meters right next to db/met- nice and easy!)

Just wondering about the water!?

NEXT QUESTION:

cheap mains down-lighters that don't have a terminal to connect a cpc into!

Am I correct in thinking if I just keep the cpc continuity and stick them in a connector block and the metal down-lighters is class 2 double insulated.....all is OK?

chrish_1977 · Feb 16, 2013

With the water you need to do a long lead check to see what is connected, it may be copper above the floor but could be in hep under the floor (my house), at very least there should be a main Bond to the water.

Second, your downlights If they say in the instructions that they are class 2 then the earth should not be connected to the fitting but maintained across the whole circuit, but if not class 2 then they need to be earthed

Jay Sparks · Feb 16, 2013

If the mains water pipe enters your house in a plastic pipe, then you probably wont need to bond it. However, as chrish has said, you may want to do a test just to make sure. Just to add, slightly off topic, alot of houses around my way are have there gas mains upgraded and the main pipe to the house from the street is going to be run in plastic, so this would also not need bonding.

And again as chrish says, if the downlights are class 2, then you dont connect them to earth but you still need to keep the earth continuity going to the rest of the lights on the circuit.

Jay

itselectric · Feb 17, 2013

Jay Sparks said:
If the mains water pipe enters your house in a plastic pipe, then you probably wont need to bond it. However, as chrish has said, you may want to do a test just to make sure. Just to add, slightly off topic, alot of houses around my way are have there gas mains upgraded and the main pipe to the house from the street is going to be run in plastic, so this would also not need bonding.

And again as chrish says, if the downlights are class 2, then you dont connect them to earth but you still need to keep the earth continuity going to the rest of the lights on the circuit.

Jay

Jay, am I reading your post right. you say not to bond gas if plastic pipe coming into building. As far as i'm aware you don't bond the incoming gas pipe at a building, the bond is for the pipework within the building, same goes for water if the pipework is metal within the building.
If I've read you wrong then sorry.

telectrix · Feb 17, 2013

itselectric said:
Jay, am I reading your post right. you say not to bond gas if plastic pipe coming into building. As far as i'm aware you don't bond the incoming gas pipe at a building, the bond is for the pipework within the building, same goes for water if the pipework is metal within the building.
If I've read you wrong then sorry.

and if the metal pipes in the building can't introduce an exterlal ( e.g.earth ) potential???????>??>

Geoffsd · Feb 17, 2013

Would agree but why does 544.1.2 say that pipes with insulating section should still be bonded on consumer's side?

itselectric · Feb 17, 2013

There is still potential of a gas fitter/plumber coming along and installing metal pipework, that being the case then the equipotential bonding should be in place.
There is a thread somewhere on this forum questioning whether plumbers and gas fitters are made aware of the electrical regulations regarding equipotential bonding and cross bonding. I don't kknow if they are informed of electrical regs involving their work the same as we are not made aware of their regs

Jay Sparks · Feb 17, 2013

I was talking about the external pipe from the road to the meter being changed from cast iron into plastic. No plumber or gas fitter are allowed to touch it! I also said that a test should be carried out on the stop cock/gas incomer to dertimine wether it needed to be bonded or not. As its entering the house via 10+ M of plastic pipe, I cant see it bringing in an external earth. But tests should be done to be sure. I did a rewire not so long back and the water incomer entered the building in cast iron pipe, only about 4 inch, then about 4 inch plastic pipe to the stop tap, then 4 inch of copper pipe from stop tap, then plastic pipe from there to everywere in the house. I didnt test it but I probably didnt need to bond it as there was only a small section of copper pipe coming from the stop cock but as it was near the new cu, I bonded it anyway.lol