Gas bonding

[Ruairi Hansen]

Hi guys just wondering what peoples thought is on this. I was out looking at a job today and noticed the main gas pipe is not bonded at the meter but has a 10mm earth at the boiler is this a code c2, c3 or nothing?

 

[Strima]

What were your test results? Is the incomer plastic?

 

[Ruairi Hansen]

What were your test results? Is the incomer plastic?

I was getting 0.04 which is fine as it is below the 0.05 value another electrician suggested putting a earth spike in beside it
[automerge]1576176438[/automerge]

I was getting 0.04 which is fine as it is below the 0.05 value another electrician suggested putting a earth spike in beside it

It's just as it is not within the 600mm of entering the building I wasn't sure

 

[telectrix]

if it's a good connection then i'd code it at worst a C3, or maybe just a comment on the report.

 

[Ian1981]

I was getting 0.04 which is fine as it is below the 0.05 value another electrician suggested putting a earth spike in beside it
[automerge]1576176438[/automerge]

It's just as it is not within the 600mm of entering the building I wasn't sure

The measured resistance of the main protective bonding conductor does not require to be 0.05 ohms or under, but the measured result should reflect the assumed length of the conductor

 

[telectrix]

The measured resistance of the main protective bonding conductor does not require to be 0.05 ohms or under, but the measured result should reflect the assumed length of the conductor

this 0.05 ohms is so much misunderstood, even by experienced sparks. it actually refers to the resistance between the end of the bonding cable to the metal pipe to which it is bonded. i.e. the resistance of the clamp. it's to prove that the bonding conductor is securely connected (electrically) to the extraneous pipe.

 

[Ruairi Hansen]

this 0.05 ohms is so much misunderstood, even by experienced sparks. it actually refers to the resistance between the end of the bonding cable to the metal pipe to which it is bonded. i.e. the resistance of the clamp. it's to prove that the bonding conductor is securely connected (electrically) to the extraneous pipe.

Cheers I always had it in my head you had to get a reading of 0.05 ohms or below.

 

[telectrix]

Cheers I always had it in my head you had to get a reading of 0.05 ohms or below.

yes, but from cable to pipe at bonding location. nothing to do with resistance of the cable itself.

 

[Ian1981]

this 0.05 ohms is so much misunderstood, even by experienced sparks. it actually refers to the resistance between the end of the bonding cable to the metal pipe to which it is bonded. i.e. the resistance of the clamp. it's to prove that the bonding conductor is securely connected (electrically) to the extraneous pipe.

Thing is they teach this at college that it is required to be below or equal to that value, as I have put a number of our apprentices right on the subject.
The worst thing is they can only quote gn3 which is bizarre as gn3 explains what you have said and that it is not from the MET to the bonding conductor.

 

[multimick]

it's 600mm ,or as close as is reasonably practical so it says in regs.
as an aside i had a disagreeement with wet pants who said my gas bond was wrong . he said it should be bonded at meter and not where it enters house, which is a few metres away i said my names on cert so it gets bonded where i say so