Sub Board fed from a plug top, EICR Coding

[Ryan G]

also depends on the 1.5mm flex. the 1363 fuse will carry a fair overcurrent for a while, causing the flex to overheat. giong by the 20A A/C load, i might lean towards a C2. what if the flex happened to be on the floor and a rug placed over it?

The flex cable won’t be covered, it’s in a kitchen cupboard drilled directly through the wall and into the sub-board - roughly 60cm length of cable.

The socket it’s plugged into is on a 4mm cable radial backed up by a 16A MCB at the main board.

I want to C2 it but am finding it hard to pinpoint why according to BS7671.

Moving forward, would it be acceptable to extend the existing 4mm cable to feed the new board? Or should a sub main have a dedicated supply?

 

[westward10]

In theory the 13A fuse is adequate protection for the plug and 1.5mm cable (not thermally insulated), and so what is down-stream is not a concern load-wise (just as you would have for an 8-way distribution strip, etc).

In practice we all know that most 13A plugs don't last long if run at or above the 13A fuse rating and will end up showing signs of thermal stress, possible also damaging the socket outlet they are plugged in to.

Still it would seem to be reasonable to at least mention it in the report. Coding it as something such as C3 is not too far from the BPG#4 guidance:

• Socket-outlet mounted in such a position as to result in potential damage to socket, plug and/or flex.

That Guide reference is citing a socket outlet location whereby its position is likely to result in damage to the socket, for example if it is too close to the floor. It does not apply to this situation.

 

[westward10]

The flex cable won’t be covered, it’s in a kitchen cupboard drilled directly through the wall and into the sub-board - roughly 60cm length of cable.

The socket it’s plugged into is on a 4mm cable radial backed up by a 16A MCB at the main board.

I want to C2 it but am finding it hard to pinpoint why according to BS7671.

Moving forward, would it be acceptable to extend the existing 4mm cable to feed the new board? Or should a sub main have a dedicated supply?

Why are you Coding it at all.

 

[pc1966]

That Guide reference is citing a socket outlet location whereby its position is likely to result in damage to the socket, for example if it is too close to the floor. It does not apply to this situation.

I known, what it is saying is if on inspection you see the socket is likely to be physically damaged, report it.

To me if you see it might be thermally damaged by its use, it is much the same. After all, if you see an already thermally damaged socket it would be a C2 as needs replacing.

 

[westward10]

I known, what it is saying is if on inspection you see the socket is likely to be physically damaged, report it.

To me if you see it might be thermally damaged by its use, it is much the same. After all, if you see an already thermally damaged socket it would be a C2 as needs replacing.

If that is how the Guide quotes it then it is referring to position nothing else.

 

[Ryan G]

Why are you Coding it at all.

Because in my eyes the conservatory is part of the dwelling, and I feel as tho the sub board was a cheap/quick way of supplying power to it.

An EICR is meant to give an electrical engineering overview of if a system is safe for continued use and I don’t want any potential problems to fall back onto my shoulders.

 

[westward10]

It isn't part of the fixed electrical installation.

 

[loz2754]

I would treat it like any other DB
List the supply characteristics, incoming fuse type and rating etc.

It is in many ways similar to a caravan or temporary building.
Fixed wiring and distribution, fed from a socket that is part of a larger installation

I agree with James.

I understand also why some might say to ignore it, because it's not part of the fixed wiring. But neither is this just an extension lead being used for normal purposes. There is a consumer unit fed from it. This consumer unit and its final circuits are items of fixed wiring and so should be treated accordingly in my view.

If the inspector chooses not to view it as such, then surely it should be included in the extent and limitations, at least.

 

[Ryan G]

It isn't part of the fixed electrical installation.

Correct it technically is not, but the fact it was put in like this shows me it should be and surely should be my responsibility to highlight?

I agree with James.

I understand also why some might say to ignore it, because it's not part of the fixed wiring. But neither is this just an extension lead being used for normal purposes. There is a consumer unit fed from it. This consumer unit and its final circuits are items of fixed wiring and so should be treated accordingly in my view.

If the inspector chooses not to view it as such, then surely it should be included in the extent and limitations, at least.

My thoughts exactly.

So can anybody see an electrical safety reason as to get rid of the plug top and instead extend the the 4mm radial (which already supplies 3 sockets) to supply the sub board?

 

[7029 dave]

I agree with James.

I understand also why some might say to ignore it, because it's not part of the fixed wiring. But neither is this just an extension lead being used for normal purposes. There is a consumer unit fed from it. This consumer unit and its final circuits are items of fixed wiring and so should be treated accordingly in my view.

If the inspector chooses not to view it as such, then surely it should be included in the extent and limitations, at least.

And to add if that CU was ever changed it would be a notifiable job too. lol

 

[westward10]

Of course you can mention it but you will have difficulty putting a Regulation against it as it is outside the scope of BS7671.

 

[Deleted account]

Got to admit this is a tricky one.

ive done loads of EICRS where there are numerous extension leads.

I always put in comment.
Excess number of extension leads in property possibly due to insufficient number of sockets. This EICR does not include testing of these extension leads and All testing done with them unplugged. C3 potential for over load If extensions are all in use.

this one is different. A CU from a plug Feeding numerous circuits.

I think the bigger question is test or not to test.

me. To cover my arse. I’d say don’t test and state that in extent installation tested.

 

[Zerax]

Very interesting thread... it may have highlighted a glaring big hole in the regs !

IMHO... if I was doing the EICR... I would have to mention it somewhere, simply ignoring it would not be an option. If there was no evidence of overheating/damage and it was correctly fused with a proper fuse (not some obvious Chinese fake), I'd give it a C3... I can see the arguments for ignoring it though.

 

[telectrix]

re-jig the feed to the sub from it's own dedicated MCB. (6mm cable on a 40A. RCD protected??). but that's not in your remit of doing a EICR. quote it.

 

[Deleted account]

Just had a though. Because it’s on a plug top and bottom would a PAT tester be needed? or would they say it’s not in there remit?
if it is in there remit do they test the plug only?
if they do test the plug only,
Who tests the circuits and board?
not us as it’s not part of the hard wired installation.

lots of questions no answer.