May not need (main) bonding, then.
Question about earthing
- Thread starter nanuuk
- Start date
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Oh dear - have you forgotten that there are many around here who like challenges?Yes it does.I agree totally with that - but just because there's no debate to be had from you, that doesn't meant that there's no debate to be had
Like that JohnW2 you mean?
Usual plumber stories, if one of the bonds gets damaged / removed / whatever the other(s) remain intact. Increased CSA. Easier to move if one of the services get moved. Easier testing. Nicer MET.
It is not permitted to bring a meduim / high pressure plastic supply pipe inside a building. It is permitted for a plastic pipe to supply a meter in an external meter cabinet, but the pipe must be metallic after that.
That's why I asked "Are you (OP) sure?" but I'm sure RF knows what he has.
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I'll take a photo tomorrow
He's not on the challenging side on this occasionLike that JohnW2 you mean?Oh dear - have you forgotten that there are many around here who like challenges?
That's surely also true with a looped (continuous) bond, unless the plumber actually cuts the conductor?
Hmmm. True, but if one of the conductors is deemed to have adequate CSA for the purpose (i.e. to render the installation safe), then increasing beyond that doesn't really confer any particular advantage.
Arguable, I suppose, even if pretty minor! I'm not so sure about the 'nicer MET' - why is having one main bonding conductor 'less nice' than having two?
Kind Regards, John.
When I filled in the trench it certainly behaved like MDPE hose. Grey IIRC. SGN laid it down, so I hope they know what they're doing!
So are you saying that what actually enters your house (as opposed to what enters the external meter cabinet) is copper?
Kind Regards, John.
I'm not saying SGN don't know what they are doing.
The point is that if the supply pipe is plastic then 'your' copper pipe may not need main bonding.
This could be why it was not bonded.
It would have to be confirmed by testing.
Presumably, beyond the fitters who installed your boiler.
It was bonded. At least to the earth rod. I don't understand the theory behind why that's wrong but I'm prepared to accept that it is!
The job is long finished and paid for, so I doubt I'll get them back as they'll be unlikely to admit there's any issue. So if it doesn't need the bonding (to be confirmed by testing) should I then remove the earth rod that's now in place? That rod will possibly connect the earth pin of the boiler supply socket, via the chassis, through the supply pipe to the ground outside the property, which according to this:
...is not good. So might I have to remove that rod?
People say all sorts of things.
I often see new gas supplies connected by a new earth rod (On TNS).
Crazy - possibly makes it worse than it already is.
Should be one earthing system per installation (whether rod or suplliers cable or even a combination) but all your earths including main bonding connected to this one earthing system (pref via your MET) .
Not your system on suppliers cable but your gas pipe on a rod , that is inviting two potentials
Crazy - possibly makes it worse than it already is.
Should be one earthing system per installation (whether rod or suplliers cable or even a combination) but all your earths including main bonding connected to this one earthing system (pref via your MET) .
Not your system on suppliers cable but your gas pipe on a rod , that is inviting two potentials
One of the people who were involved with moving my gas meter mentioned some meter readers have reported getting a noticable tingle when they have touched an external gas meter. Maybe putting a ground rod to the meter is a result of this.
I wouldn't say it was crazy, it is only adding another ground point to the MET which is "connected to ground" via the neutral of a PME system or putting another rod in parallel with the rod(s) in a TT system.
Above all it reduces the risks of shock to meter readers ( and any one else who touches the gas meter ) when the internal bonding / earthing is not fitted, has failed or been tampered with. Or when the network has faulted and the neutral has dangerously high voltages. Inside equipotential zone people are "safe" but bonded items that can be touched by people outside the zone will be a serious shock hazard.
No Bernard lad that is back to front.
We tie all earthy stuff together to ensure it is at the same potential.
Wherever we go on this planet of ours there is always a difference of electrical potential between any two points.
Therein lies the problem.
You're gas/water/oil/steel structure incoming supply could be at a different potential to your electrical earth.
We connect them all together with a sizeable conductor to help ensure they are all at substantially the same voltage whatever that voltage may be.
Unfortunately we do not all live on a big thick conductive metal plate like the Daleks used to, and different services could be at quite different earth potentials, hence the danger.
If your gas supply is metal and in contact with the local earth then it will be at local earth potential, if it is isolated in some way and you rod it to local earth then you might make the danger worse not better .
If you connect your locally earthed stuff (Gas/water etc) to electrical earth (which could be derived from an earth appreciably far away therefore a different potential) than you are holding down the touch voltages between the two.
Your incoming electrical "earth" might be above local "earth" by say 35 volts before any faults on a good day. Using the N cable for earthing rather than a separate E cable as we do in PME makes that more likely.
Your previous example of rod to services does not improve the situation but it might well make it worse.
Join them robustly together and you have got a chance.
We tie all earthy stuff together to ensure it is at the same potential.
Wherever we go on this planet of ours there is always a difference of electrical potential between any two points.
Therein lies the problem.
You're gas/water/oil/steel structure incoming supply could be at a different potential to your electrical earth.
We connect them all together with a sizeable conductor to help ensure they are all at substantially the same voltage whatever that voltage may be.
Unfortunately we do not all live on a big thick conductive metal plate like the Daleks used to, and different services could be at quite different earth potentials, hence the danger.
If your gas supply is metal and in contact with the local earth then it will be at local earth potential, if it is isolated in some way and you rod it to local earth then you might make the danger worse not better .
If you connect your locally earthed stuff (Gas/water etc) to electrical earth (which could be derived from an earth appreciably far away therefore a different potential) than you are holding down the touch voltages between the two.
Your incoming electrical "earth" might be above local "earth" by say 35 volts before any faults on a good day. Using the N cable for earthing rather than a separate E cable as we do in PME makes that more likely.
Your previous example of rod to services does not improve the situation but it might well make it worse.
Join them robustly together and you have got a chance.
Sorry Bernard I think I misread you.
Seems you are correct - the rod might have caused this tingle
Seems you are correct - the rod might have caused this tingle
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