In the absence of any other bonding, all of the pipework in the building would be 'floating', which is hardly a desirable situation.
Au contraire, it is very desirable to have pipework electrically floating as there is no path for current to flow
In the absence of any other bonding, all of the pipework in the building would be 'floating', which is hardly a desirable situation.
Although rather futile on account of the service already being bonded at your meter (unless you're looking at a huge length of pipe with a significant electrical impedance), ....
I certainly can't disagree with that......there is no doubt that this (and any) conductive pipework between your and your neighbour's property is an extraneous conductive part. If it were me, I'd bond it again within 600mm of where it exits your property/enters your neighbour's.
Hmmm ... in a guarantreed totally earth-free enviroment, that might well afford some reasurance. Within any other environment, it's all well and good until some fault connects all that floating metalwork to a hazardous potential, and then some unwitting human being manages to provide a path for current to flow along!Au contraire, it is very desirable to have pipework electrically floating as there is no path for current to flow
Now you are mixing up earthing and bonding.
Yes, I understand that - but in the absence of any other bonding, the only thing which could be dangerous, and which the present MPB renders safe(er), is the 300-400mm of pipe between the water meter and the flow sensor. However, I'm not denying that even that little bit of pipe should be safe.A metal pipe coming out of the ground is at a potential.
The earth coming into your house may be at a different potential.
If these are not bonded together then there may be a potential between them which would be dangerous. That is why bonding is carried out, and that is why it is done as close to the point of entry to your property as possible.
I understand that such is not the primary purpose of the MPB. However, I want my pipework effectively earthed (don't you?) and in the vast majority of properties that is achieved (or supplemented/ enhanced), 'accidentally', by the MPB - it is merely the presence of a plastic interruption early in my pipework which stops that being the case for me.It has nothing to do with earthing your installation pipework ....
Technically, yes, in relation to that 300-400mm of pipework. That's why I'm proposing attaching the MPB on both sids of the flow sensor (which at least SOME people here seem to agree is acceptable) rather than moving it. Let's face it, apart from removing the need for one additional screwed clamp connection, what I'm talking about is effectively no different from leaving things as they are and upgrading the cable across the flow meter to 10mm².It has If you move your MPB to the other side of your flow sensor than you are leaving a piece of metal in your house which is at a different potention to all the other metal work in your house.
You would have made a perfectly safe installation dangerous.
It is certainly compliant. By virtue of other bonding (and the gas pipe), it is also probably pretty safe - but, provided it is not contrary to the regs (and it seems that it isn't) why not enhance that safety with the redunancy (which almost everyone but me already enjoys) of having the MPB add belts and braces to the earthing of the installation pipework?Your installation is safe and compliant. Leave it alone.
As I've written elsewhere, I'm not mixing them up. I'm merely trying to enjoy the same 'accidental/incidental' enhancement to earthing of pipework which most people enjoy as a a secondary consequence of having an MPB - and just wanted to confirm that it would not offend the regs. It is that 6 inches of plastic a metre or so from my water meter which makes me different from most other people ... and I can remove that inequality simply by attaching the same (existing) MPB to the pipe on my side of the plastic, as well as retaining its existing connection close to the meterNow you are mixing up earthing and bonding.
It all comes down, or should come down, to common sense. No, there is no 'requirement' for all exposed metal pipes etc. to be earthed - but I want mine to be earthed where practical (don't you?) - and the required MPB represents the most robust 'earthing' of pipework installations in most households (other than mine!), and I want to remedy that; that's all I'm saying.There is no requirement to "earth" water pipes, central heating pipes etc within your house.
There is a requirement to main protective bond extraneous conductive parts as they enter the equipotential zone.
If your electrical installation is so bad that it can short to the pipework then it needs urgent attention!!
If you started earthing tag lag where would you stop, would you earth each radiator on a wet plastic piped C/H individually as someone may catch a flex on it?
I haven't looked it up (again) today but I think you will find it is a suggestion or a recommendation of good practice, not a regulation. Last time I looked I noticed the absence of the word "must" and I think it said "should" or similar. Regulations say "must." I used to write things like that.Which regulation calls for MPBs to remain unbroken?
It is mentioned in BS7430, part 21.4
Which regulation calls for MPBs to remain unbroken?
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