Help! Never seen this before!

[Steve93]

I am installing solar to a house and this is there main incoming. I can’t see an Earth anywhere but test ZS across L-N coming out at 0.20. Then with gas bond disconnected is 0.38! But we only have gas bonding. No other earth anywhere. Anyone had this?

 

[Pete999]

A pic of the gubbins in the CU might help!

 

[Deleted account]

What about a pic of the main earth terminal in the cu.

Still waiting for that pic....

 

[telectrix]

A pic of the gubbins in the CU might help!

wayayy too technical as it's way past beer o'clock.

 

[Pete999]

Still waiting for that pic....

Yeah whats's apnin OP get a grip will you

 

[Steve93]

I’ve explained. There are final circuits and one 6mm which goes to the gas bond only! Nothing else no main earth nothing. Just the earths from the circuits

 

[Deleted account]

Is the consumer unit metal. Is that bonded to earth via the casing. Need photos.

 

[DPG]

Not sure if anyone has thought of it, but we could do with photos.

 

[Pete999]

Not sure if anyone has thought of it, but we could do with photos.

Keep up Mate please

 

[Steve93]

It’s an old domino db. Plastic. I’m off site now and couldn’t keep turning power off to take pics inside.

 

[davesparks]

DNO don’t seem to care! They bassicly told me to put it on a TT system. They can send someone out to see if it can be changed to PME but that’s a 5 week waiting time.

Did you explain to them that there’s an unearthed cast iron cutout with open holes in the top exposing live parts?
The TT/PME answer sounds more like the standard response to asking for an earth connection rather than reporting this situation.

 

[Octopus]

Maybe seek the advice of your boss - I see you have trainee access.

 

[buzzlightyear]

the op needs to get DNO in to have a look at it ,if he is in doubt.
test at the cu and test for a earth on old DNO isolators . what's the betting their is a earth some where .ring up Scottish and south Elecs.

 

[b-spark]

I've seen it before, inside the cast iron isolators theirs a rewireable fuse, what your seeing is a split supply for another building aswell as yours. Back in the 50's it was also acceptable to use the gas as the earth. The meter fitter wants reporting, but it is upto the electrician to give a earth. is it a rural location?

 

[Steve93]

Did you explain to them that there’s an unearthed cast iron cutout with open holes in the top exposing live parts?
The TT/PME answer sounds more like the standard response to asking for an earth connection rather than reporting this situation.

Yes explained clear as day she just put me on hold and then went on to say they can send someone out in 5 weeks.

 

[Steve93]

Maybe seek the advice of your boss - I see you have trainee access.

Yes but something I’d rather find out for myself. He is well aware but I like to look into these things so I know for future reference etc.

 

[Steve93]

I've seen it before, inside the cast iron isolators theirs a rewireable fuse, what your seeing is a split supply for another building aswell as yours. Back in the 50's it was also acceptable to use the gas as the earth. The meter fitter wants reporting, but it is upto the electrician to give a earth. is it a rural location?

If that’s the case how come I can’t get any earth reading off the casing?

 

[buzzlightyear]

Yes explained clear as day she just put me on hold and then went on to say they can send someone out in 5 weeks.

tell them that you will wait a couple of months if they want .

 

[buzzlightyear]

Yes explained clear as day she just put me on hold and then went on to say they can send someone out in 5 weeks.

tell them that you will wait a couple of months if they want .

 

[Octopus]

Yes but something I’d rather find out for myself. He is well aware but I like to look into these things so I know for future reference etc.

I've given you a disagree because learning from experienced sparks is what a boss is for............

 

[Steve93]

I've seen it before, inside the cast iron isolators theirs a rewireable fuse, what your seeing is a split supply for another building aswell as yours. Back in the 50's it was also acceptable to use the gas as the earth. The meter fitter wants reporting, but it is upto the electrician to give a earth. is it a rural location?

If that’s the case how come I can’t get any earth reading off the casing?

 

[ipf]

If that’s the case how come I can’t get any earth reading off the casing?

Anywhere?
Checked that incoming lead sheath?

 

[Steve93]

Anywhere?
Checked that incoming lead sheath?

Yep anywhere every screw every bit of rust every nut

 

[b-spark]

If that’s the case how come I can’t get any earth reading off the casing?

sorry, off the enclosure? That wont be earthed. The installation wont be earthed full stop. its a TT Job, I would actually report it to the DNO. The cut out fuses inside are normally only 40-60amp

 

[Steve93]

Look I’m an adult learner. I have experience but I have not come across something like this. This is why I have written on here for advice. Now some people are just saying call DNO some are saying just TT it. Surely DNO need to see it and change it as it is so old? Or am I wrong and it’s fine and I just need to supply my own Earth? And TT the whole house?

 

[ipf]

Look I’m an adult learner. I have experience but I have not come across something like this. This is why I have written on here for advice. Now some people are just saying call DNO some are saying just TT it. Surely DNO need to see it and change it as it is so old? Or am I wrong and it’s fine and I just need to supply my own Earth? And TT the whole house?

Good call. I agree....DNO. Tell them it's old and there's danger involved.

 

[ruston]

Call the DNO . You are unhappy with it . It is the right thing to do .
You have to report on it's condition.

 

[telectrix]

contact DNO , ask for the duty engineer, not some nail polishing tart who knows diddly squat. tel him that you suspect fused neutral.

 

[markythesparky]

I am installing solar to a house and this is there main incoming. I can’t see an Earth anywhere but test ZS across L-N coming out at 0.20. Then with gas bond disconnected is 0.38! But we only have gas bonding. No other earth anywhere. Anyone had this?

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Unless I’m missing something I do t see what the problem is. I’ve come across this situation a few times.

You will of course get a loop impedance reading to neutral as the neutral will be connected to earth at the sub station.

In days of yesteryear the gas could be used as the main earth but since the advent of yellow plastic pipes this is not allowed. Water too was used but stopped for the same reasons.

DNO’s have become increasingly less interested in the earthing set up of a property. Even as recently as 25 years ago it was said that he earthing was the responsibility of the consumer. Unless there are live parts exposed at the DNO’s equipment they won’t bother to treat it as urgent.

Easiest solution is to convert the system to a TT and carry on.

 

[davesparks]

Back in the 50's it was also acceptable to use the gas as the earth.

I don’t think it was, as far as I can remember all the old regs books I’ve got don’t allow the use of pipes carrying flammable fluids.

 

[ipf]

Unless I’m missing something I do t see what the problem is. I’ve come across this situation a few times.

You will of course get a loop impedance reading to neutral as the neutral will be connected to earth at the sub station.

In days of yesteryear the gas could be used as the main earth but since the advent of yellow plastic pipes this is not allowed. Water too was used but stopped for the same reasons.

DNO’s have become increasingly less interested in the earthing set up of a property. Even as recently as 25 years ago it was said that he earthing was the responsibility of the consumer. Unless there are live parts exposed at the DNO’s equipment they won’t bother to treat it as urgent.

Easiest solution is to convert the system to a TT and carry on.

That's bull...
The incoming equipment is owned by the supply authority. If any danger occurs it's their responsibility.
They may have less interest but that doesn't mean they aren't responsible.

The equipment is old and, especially looking at the ceramics involved, requires an upgrade.
I've had quite a few changed over the years.