Is this really correct?

[Sparky83]

Hi guys,

On a forum i often go on someone was asking about the MEB to there gas pipe as the gas engineer had pointed out that there was bonding to both side of the gas meter.

Someone asked this question...

Aren't gas mains plastic too? What is the earthing for, to protect those inside the property from an issue that causes the pipework to become live?


Somebody whom says they are an electrician said the following...

its to stop external influences affecting your metal work essentially, nowadays most incoming gas/water bonds are plastic and don't need the equipotential bonding to them but most sparkies do it anyway, just disconnect the before clamp wire and put it in the post clamp terminal, easy job and should take 2 mins. nothing will happen when you remove it, just make sure its tight enough not to pull out and the clamp should not spin on the pipe either

Now is this correct? As im pretty sure that you always need the MEB to be in place?

I did question this with him and his reply about did he mean supps was...

main bonds too, i know it seems crazy to me too, it come up on my last nic inspection i went to.

he asked why i bonded main earth and water when they was plastic incoming. if its not metal incoming into the property the the metal work is inside is classed as supplementary, (not required now) he then proceeded to ask me how i would get a shock from metal work if it wasn't even connected to the "installation" with so many instances where continuity cannot be obtained on all pipe work then there should never be a potential difference between materials. hence no bonds no difference. obviously all circuits in said install have to be 30ma rcd protected

(again im no lecturer but those who have niceic inspections know how ---- they can be, so only going on what im told)

Hope it makes sense, Any thoughts on the above?

 

[Engineer54]

Yep,Water has its uses mixing with those charged electrons

This is one that surprises the sceptics
'Hot-Washing' the Insulators of a 500,000 Volt Power Line! - YouTube

I've had a go at that myself, scary at first shot, ...then fun!! But i might add Not at 500K volts, just 33KV and 66KV. It's the standard way of cleaning lines and insulators. One guy here doesn't believe they use this method, for cleaning MV/HV transmission lines, ...just been proved very wrong hasn't he!! lol!!

 

[Des 56]

I've had a go at that myself, scary at first shot, ...then fun!! But i might add Not at 500K volts, just 33KV and 66KV. It's the standard way of cleaning lines and insulators. One guy here doesn't believe they use this method, for cleaning MV/HV transmission lines, ...just been proved very wrong hasn't he!! lol!!

Must admire you for doing that

Even being aware of the properties of water and its interaction with electrics I still wouldn't do it :blush5:
Go up in an hellicopter I mean ,of course lol

 

[Knobhead]

DW water is not as conductive as you might think. Great bit on it in kitchers book. It increases in conductivity with additives but not much.

Try telling that to one of these.
View attachment 10568
A liquid resistor.
Add salt or caustic soda to the water and the resistance falls dramatically. Great fun until they go wrong!