Gas meter earthing

[Essex1]

Yes. All main bonds can go back to the DB. This is usually the case. 

 

[Blue Duck]

 

[SLIPSHOD & SLAPDASH]

Yes. All main bonds can go back to the DB. This is usually the case. 

Not quite, they go to the main earth terminal that can be inside or independent to the  consumer unit.

 

[Essex1]

I didn't say always.  :B-

 

[Davethsparky]

Essex's statement is only partially correct. You should have either; two individual bonding conductors from water and gas back to electrical earth, or you can have one continuous (unbroken) bonding conductor looping both gas and water back to electrical earth. But it must not be electrical earth to pipe'A' then second bonding conductor from pipe'A' to pipe'B'. So if the pipe clamp at the water pipe was disconnected there must still be earth continuity to the gas pipe.

Doc H. 

Why not? Did they remove the use of metallic pipes as a bonding conductor from the regulations?

 

[Manator]

Why not? Did they remove the use of metallic pipes as a bonding conductor from the regulations?

The regulation is very simple in terms of application. The reason for a continuous connection is that the one cable will still be connected to one or the other when disconnected, for testing or maintenance purposes.

If you have (a link) then when disconnected from the first point, no connection to earth  will be found at the second.

They have never applied a rule that pipes form part of the bonding process, and as such have never been accepted or considered suitable as a bonding link.

Yes the pipes do provide a link, but are never relied upon to provide that link, which is why we bond them.

Then we have another problem, we are all capable and guilty of introducing a potential when none exists! Water and gas were originally bonded because they had a potential to earth. Modern installation methods utilise plastic pipes and pose no potential to earth but are still bonded at the required distance.

Most of us that have been in the game for a while would have come across a gas installer  who diligently uses a earth link to change a meter for example. He does not firstly establish a suitable earth, he does not need to, because all he is doing is maintaining the potential between the connections, and preventing any build up of static.

 

[Davethsparky]

They have never applied a rule that pipes form part of the bonding process, and as such have never been accepted or considered suitable as a bonding link.

543.2.1 (vii) allows extraneous parts to be used as protective conductors (subject to certain conditions) which encompasses both practice bonding conductors and circuit protective conductors. This has existed in various forms in the regulations for many years. 

 

[Doc Hudson]

543.2.3 Prohibits the use of Gas pipes as a protective conductor, so you cannot go MET to Gas then separate Gas to Water. And 528.3.3. refers to any foreseeable work on non electrical services impairing the integrity of the electrical installation. Such as the plumber deciding to put a plastic branch between your two bonding connections. At the end of the day it is your risk assessment of the jobs you do and how you interpret BS7671, If something were to go wrong I think the considerations would be, was there a safer more secure option that could have been done to prevent accidental disconnection of either Gas or Water bonding. 

Doc H.

 

[ProDave]

I had an unusual one on a recent EICR

Gas meter outside. Galvanised steel gas pipe along the bottom of the wall, then up the wall into the loft, changing to copper pipe just before it entered the loft.  No visible earth outside.

Crawl into the loft, passed all the owners junk, squeeze down into the eaves, and there, under the loft insulation is the earth bond on the copper gas pipe just as it enters the loft space.

Why do I get the feeling the next gas inspector is just going to say "gas not bonded"?

 

[Evans Electric]

How close did you look , as there is a condition where one bonding cable goes from the board to the gas then, without being cut , continues to the water .  Or visa versa.

 

[Rob_the_rich]

I had an unusual one on a recent EICR

Gas meter outside. Galvanised steel gas pipe along the bottom of the wall, then up the wall into the loft, changing to copper pipe just before it entered the loft.  No visible earth outside.

Crawl into the loft, passed all the owners junk, squeeze down into the eaves, and there, under the loft insulation is the earth bond on the copper gas pipe just as it enters the loft space.

Why do I get the feeling the next gas inspector is just going to say "gas not bonded"?

might be worth putting a sticker on or near the gas meter stating location of gas bond next time. Could save a re-visit for someone. Although odds are the gas operative would just write "not within 600mm" anyway

 

[NozSpark]

I had an unusual one on a recent EICR

Gas meter outside. Galvanised steel gas pipe along the bottom of the wall, then up the wall into the loft, changing to copper pipe just before it entered the loft.  No visible earth outside.

Crawl into the loft, passed all the owners junk, squeeze down into the eaves, and there, under the loft insulation is the earth bond on the copper gas pipe just as it enters the loft space.

Why do I get the feeling the next gas inspector is just going to say "gas not bonded"?

My patents had that, almost,  exact scenario.... I bonded it in loft,,,,, BG meter monkey comes to fit smart meters and says gas isn't bonded... so my father tells me and we have that backward forward thing of me telling him that it's bonded in loft :shakehead

 

[ProDave]

Surely if the next upgrade of the wiring regs could do just one thing that's remotely useful, it would be to update the electricians bonding regs and the gas man's bonding regs so they were actually the SAME.

 

[Andy™]

Surely if the next upgrade of the wiring regs could do just one thing that's remotely useful, it would be to update the electricians bonding regs and the gas man's bonding regs so they were actually the SAME.

that would need LFB approval

 

[Lusk]

This 600mm 'rule' is people taking the regs (544.1.2) too literally, note the keyword - practicable!

The before any branches make sense and near to the meter.  I reckon the 600mm thing just loosely defines a 'standard' location for the connection, so it can be readily locateable.

 

[Sidewinder]

Plus the GSIUR do not specify a distance, they defer to the electrical regulations.

A little Internet Searching will find a 4 page article in one of the plumbers trade magazines by an electrical person, that tells them that bonding in the property in accordance with BS7671 is preferred over bonding in the meter box when the meter is outside.

However, they are required to check that the bonding is there and correct in the same way we are, but, they are just not competent to verify it electrically really.

 

[Essex1]

This 600mm 'rule' is people taking the regs (544.1.2) too literally, note the keyword - practicable!

The before any branches make sense and near to the meter.  I reckon the 600mm thing just loosely defines a 'standard' location for the connection, so it can be readily locateable.

The 600mm thing comes direct from the 16th Edition OSG. I am unsure whether it is in the 17th Edition OSG because I do not own one. 

 

[Sidewinder]

IIRC it comes from before the 16th OSG.

However, I ain't digging out any earlier editions at this time on a Saturday night!

It's actually currently from reg 544.1.2

 

[Manator]

I remember it from the 15th certainly not too sure about the 14th as I was only an apprentice then.

the 600 mm rule was so that there was a set standard were people could look, however the word practical still remains and I have often deviated so that the bonding is very clear and evident and more importantly available for inspection.

 

[Essex1]

Well seeing that all meters are accessible then it would difficult to see a situation in which it was not 'practical' to bond within 600mm.