Bonding

[chronyx]

I have done a P.I.R./C.o.S.R on a commercial unit and could see no earth tags on exposed pipework.

The incoming water supply pipe is plastic and therefore not introducing earth potential.

I checked using a long lead between the pipes, sink, and taps and there was no continuity to earth.

Am I therefore correct in assuming this meets the regulations?

Also the main earth conductor has been split into two to go into the M.E.T. in the isolator. Pic attached. I assume this is frowned upon?!

Cheers guys.

 

[Farmelectrics]

buy a bigger block and mark your earths up job done for me oh collect your money and get to your next job lol

 

[malcolmsanford]

As long as you feel that the connection complies to regulation 526.1 then leave, though with it just "floating" around I would try to fix it to the case.

When you tested did you perform a continuity test or an insulation resistance test? Was any of these pipes, sinks etc in a special location? Is there any additional protection by RCD ? What was the Zs results like

 

[supasparxs]

As long as you feel that the connection complies to regulation 526.1 then leave, though with it just "floating" around I would try to fix it to the case

Malcolm, do you want to borrow my glasses, someone has used a self drilling screw to fix it to the back of the cabinet........

 

[malcolmsanford]

Malcolm, do you want to borrow my glasses, someone has used a self drilling screw to fix it to the back of the cabinet........

Looks like only 1 fixing though mate, perhaps "flapping" about rather than "floating" about, still dog rough.

 

[Des 56]

Fixed or no,the oxidised conductors paint a sorry picture

 

[chronyx]

As long as you feel that the connection complies to regulation 526.1 then leave, though with it just "floating" around I would try to fix it to the case.

When you tested did you perform a continuity test or an insulation resistance test? Was any of these pipes, sinks etc in a special location? Is there any additional protection by RCD ? What was the Zs results like

Thanks for your replies everyone, it's really useful to get another spark's opinion on something like this.

I did a low-ohms not insulation resistance, and there are no special locations just a small kitchen area and W.C. RCD times were very good, and it is a split load board with only the following circuits on the non-RCD side:

Smoke Alarm
Lights (Main Office)
Lights (Toilet/Extractor/Disabled Toilet Alarm)
Security Alarm

Having these non-RCD protected seems logical to me as you don't want these circuits affected by nuisance tripping.

 

[telectrix]

you need to IR test at 500v between MET and pipework. if the reading is >22k ohms, then no need to bond. the non-RCD circuits are only non compliant with current regs id cables buried<50mm deep without earthed mechanical protection

 

[chronyx]

Thanks telectrix, where did you get that figure? I have GN3 and On-site Guide but don't remember seeing it. Always handy to know where to look!

 

[IQ Electrical]

Fixed or no,the oxidised conductors paint a sorry picture

I was hoping they were strands from a split concentric-you may be right with the oxidised cores!

 

[IQ Electrical]

Thanks telectrix, where did you get that figure? I have GN3 and On-site Guide but don't remember seeing it. Always handy to know where to look!

The test is described in Guidance Note 8 and is derived from 230V, 10mA as the 'let-go threshold' and 1000 Ohms as the impedance of the human body.

 

[chronyx]

Thank you IQ, I didn't get a notification of your reply so I'm sorry for my delay! Much appreciated as I don't have GN8.

What is your take on the split M.E.C's?

There is another one in a D.B. and to be fair I can't see how else they could have terminated it.

But regs is regs, and I have to cover myself!

 

[Deleted member 26818]

I was hoping they were strands from a split concentric-you may be right with the oxidised cores!

That's what I was thinking.

 

[malcolmsanford]

Thank you IQ, I didn't get a notification of your reply so I'm sorry for my delay! Much appreciated as I don't have GN8.

What is your take on the split M.E.C's?

There is another one in a D.B. and to be fair I can't see how else they could have terminated it.

But regs is regs, and I have to cover myself!

Not sure what IQs take on it would be but mine is that I can not see any problem with doing it. I rather get a good mechanical sound termination by spiting the core conductor this way than trying to fit an oversize CSA into a small terminal, or even worse IMO shaving of cores to make it fit.

As long as the conductors are tight in the terminals I would be happy

Most modern CU take into account the larger earth/bonding CSA sizes so this type of situation will be gradually be phased out over the years.

 

[johnboy6083]

you can buy attachments for the earth bar, which terminates into 2 terminals, and has a tapped thread so you lug onto that. Looks nmuch more proffessional than splitting the cores