Dodgy PME?

[tudge56]

Hi, wondering if anyone can help me. Came across an installation that doesn't appear to have any means of earthing at the intake

. Some work has been done to run power to a garden workshop and the earth to this has just been terminated in with the neutral AFTER the meter.....is this allowed?? It doesn't feel right to me but can anyone quote a reg to back this up?? Thanks for the help.

 

[DPG]

Hi, wondering if anyone can help me. Came across an installation that doesn't appear to have any means of earthing at the intakeView attachment 116962. Some work has been done to run power to a garden workshop and the earth to this has just been terminated in with the neutral AFTER the meter.....is this allowed?? It doesn't feel right to me but can anyone quote a reg to back this up?? Thanks for the help.

Looks creative! Is there no earth conductor in the Wylex CU at all?

 

[James]

411.4.3
In a fixed installation, a single conductor may serve both as a protective conductor and as a neutral conductor (pen conductor) provided that the requirements of 543.4 are satisfied. no switching or isolating device shall be inserted in the pen conductor.

NOTE: regulation 8(4) of the electrical safety, quality and continuity regulations prohibits the use of pen conductors in consumers installations.

I read that as the consumers installation begins at the origin of supply (service head) the meter is part of the consumers installation, even if (as is likely) it is not owned by the consumer.

one thing is for sure the cable from the meter onwards is definitely part of the consumers installation and as per reg. above cannot be a PEN conductor.

 

[westward10]

Probably done when that MK board was put in.

 

[James]

I also have a funny feeling that the "electrician" that fitted the additional consumer unit has forgotten to put a nice label on it that says
INSTALLED WITH PRIDE BY
ABC Electrical contractors
0122 123 1234

and the certificate will be in the post when you have paid this bill with cash.

 

[timhoward]

It's also possible that whoever fitted the MK removed an up front RCD or VOELCB that was in the way.
Worth a look to see if there is a likely looking earth conductor in the Wylex.

Ultimately this is all going one of two ways:
-DNO may deign to supply an earth (free if you are very lucky, or more likely for a fee)
-or it needs an earth rod, and RCDs for fault protection

 

[littlespark]

Brand new meter? (Is it reading 0000.0?)

 

[James]

Brand new meter? (Is it reading 0000.0?)

meter is showing 0 export

 

[littlespark]

meter is showing 0 export

I need to get my eyes checked. Of course it does.


The backing board looks a bit black. You think something has been smoking a little?

 

[mainline]

542.1.2.2 For a TN-C-S system, where protective multiple earthing is provided, means shall be provided for the
main earthing terminal of the installation to be connected by the distributor to the neutral of the source of energy.

 

[tudge56]

Thanks people, all good advice. I only went to do a quote as the customer was worried that the 'electrician' might have only been a builder and wanted me to check it. I've requested a PME terminal at the cutout which Northern Power Grid normally do for free if they deem it suitable so fingers crossed! I haven't taken the front off the Wylex so there could well be an earth cable to a rod in there....couldn't see any sign of one outside the house so it'll be fun trying to find that

 

[KungFuTurkeyLeg]

Nice if they do it for free. Is it a slack criteria to qualify?

 

[tudge56]

Nice if they do it for free. Is it a slack criteria to qualify?

I don't know what the criteria is....I've made about 8 requests in my years here and only had one refused....never could find out why!

 

[mainline]

You will probably find that it's a TT and whoever did the sub main didn't want to use a rcd so decided to do what they did.

 

[pc1966]

It is possible the old Wylex install relied upon a water pipe bond for earth. Not permitted by the regs for many decades, but still occasionally seen in the wild.

 

[UNG]

I don't know what the criteria is....I've made about 8 requests in my years here and only had one refused....never could find out why!

There are certain areas where the network / local ground conditions are not suitable for PME / TNCS connections I remember talking to an ENWL jointer a few years back that in certain areas of the North West they are not allowed to put PME / TNCS connections in because the ground is very sandy and drains easily so they cannot get a reliable earth at the network joints to support PME and if they do they are at risk of being fired

 

[tudge56]

There are certain areas where the network / local ground conditions are not suitable for PME / TNCS connections I remember talking to an ENWL jointer a few years back that in certain areas of the North West they are not allowed to put PME / TNCS connections in because the ground is very sandy and drains easily so they cannot get a reliable earth at the network joints to support PME and if they do they are at risk of being fired

Ah that makes sense. And ironically I've just had a refusal back from Northern Power Grid saying they can't provide a PME connection to this property . Better look in to that earth rod........

 

[pc1966]

Ah that makes sense. And ironically I've just had a refusal back from Northern Power Grid saying they can't provide a PME connection to this property . Better look in to that earth rod........

Not just a rod, but something to deal with the Wylex board!

At the least you could add a delay RCD up front so at least you can achieve some disconnection, but really it is a case for a new CU to have some selectivity to keep the lights on if a socket faults, etc.

 

[grumpyjohn01]

It is possible the old Wylex install relied upon a water pipe bond for earth. Not permitted by the regs for many decades, but still occasionally seen in the wild.

Found a place on an EICR like this last year..and guess what? the water supply pipe had been changed for plastic..

 

[Risteard]

Hi, wondering if anyone can help me. Came across an installation that doesn't appear to have any means of earthing at the intakeView attachment 116962 Some work has been done to run power to a garden workshop and the earth to this has just been terminated in with the neutral AFTER the meter.....is this allowed?? It doesn't feel right to me but can anyone quote a reg to back this up?? Thanks for the help.

It is illegal under ESQCR.

 

[mhar]

There are certain areas where the network / local ground conditions are not suitable for PME / TNCS connections I remember talking to an ENWL jointer a few years back that in certain areas of the North West they are not allowed to put PME / TNCS connections in because the ground is very sandy and drains easily so they cannot get a reliable earth at the network joints to support PME and if they do they are at risk of being fired

Round our way we have some areas which use very old cabling originally put in when the network was DC, the joints can't withstand the high fault currentsyou get with pme.

I had a very similar job to the picture in the op. Three cottages built for the gasometer staff, no 1 was tt, no 2 homemade pme and no 3 pme from the cutout with a SWEB laminate stating pme. I was in number 2 and had poor efli so called the DNO who attended very quickly and referred this to a network planner who said I must tt it. When I showed him the laminate in no 3 he agreed that it was their issue and the 3 cottages needed to be resupplied. Some weeks later I was asked to be in attendance as the contractors had done the excavations and they were going to bring in the new supplies. The old school jointer allowed me to watch as he opened up the lead encapsulated joint, disconnected the old feeds and then used one of the new (idiot proof!) joints for the replacement supplies, the whole time he was giving me a comentary on what he was doing and explained why the old joints were not suitable for the pme fault currents. I found it fascinating and was impressed to watch a skilled jointer undertake his task

 

[UNG]

The old school jointer allowed me to watch as he opened up the lead encapsulated joint, disconnected the old feeds and then used one of the new (idiot proof!) joints for the replacement supplies, the whole time he was giving me a comentary on what he was doing and explained why the old joints were not suitable for the pme fault currents. I found it fascinating and was impressed to watch a skilled jointer undertake his task

Reminds me of one where I got the DNO in to swap a L - N fused metalclad head in a church got talking to the 2 guys doing it the guy doing most of the work having got part way turned to me and said it sounds like you know what your doing do you want to finsh it off and we'll talk you through it