Can you extend meter tails inside a consumer unit ?

[vwes59]

...and why would I want to do that ?
Well, I'm faced with a real botch job of a consumer unit. Essentially this is a "new" consumer unit only put in a couple of years ago by a friend of the clients family who was apparently an electrician. However the unit they bought (a Niglon) had the main switch on the left side, the tails were only long enough to reach the right side (Don't ask why it wasn't positioned correctly, I've no idea). So they "adapted" the unit so the main switch is now on the right side, but has a second main switch in the middle made by Eaton! which I'm assuming they thought would act as an RCD, which of course it doesn't. It's a mess inside to be honest, and I'd love to rip the thing out and start again, but I can't because its been built into the wall, and the client doesn't want to mess up the extension which has just been redecorated. It has so many things wrong with it, I've had to hand a dangerous condition notice to the client and refuse to do any work unless its put right (That's to protect me and them).

Anyway they've come back and asked me to put it right. To put it back the way it should be and get rid of the bits that shouldn't be there, the tails are not long enough, so I wondered can you extend the tails inside a consumer unit, if so what's the correct way to do it ? The 3M length would not be exceeded as the the meter is the other side of the wall, so I doubt they exceed 2M let alone 3M. As I said, I can't move the thing or probably find one that's exactly the right size for the hole in the wall, so I'm stuck with what I've got.

 

[loz2754]

Through crimps with heat shrink tubing applied.
Though to be honest, I wouldn't be trying to fix it, I'd want to start again if I'm putting my name to it.

 

[telectrix]

i'd fit new tails. end of. (only because wago don't do 25mm connectors. ??).

 

[westward10]

I would attempt to replace them. Use earthing conductor as a draw wire to pull a tape through to see how clear the void is but often this may get to the point of no return if it snags, leave the old tails in place if possible until you pull new ones in. Apart from that there is nothing wrong with crimping and sleeping.

 

[littlespark]

Henley block inside the CU.

 

[telectrix]

there is nothing wrong with crimping and sleeping.

could do with a good sleep right now. haven' been able to use rught hand since a nasty insect bite 2 weeks ago and the pain has been horrendous. just started 2nd antibiotic course as it's improved , but not right yet. impossible to use tools and have to hold pint in left hand

 

[vwes59]

Henley block inside the CU.

That's not a bad thought. Can anyone remember the name of the smaller Henley blocks, those might fit better.

 

[UNG]

For the extra few inches needed is there no spare cable at the incoming position that could be pulled through

 

[vwes59]

I'll check with regards how much I can pull through.

I've just noticed something in my original photographs, that I hadn't considered. If this MS2100 main switch was originally on the left of the board, then the connections on the bottom would be Neutral to the left, and Line to the right to connect into the busbar. If I'm right then the whole board has got its polarity reversed ! I've just checked a few photographs online concerning the insides of Niglon boards, and most have the main switches on the left and the connectors on MS2100 switches are Left-Neutral, Right-Line

 

[littlespark]

Some of the left hand mainswitch CUs I’ve seen just have an extended busbar to get the line past the neutral.

I don’t know why they never started off with mainswitch on left, and counted the circuits left to right? Even back with rewirables.

 

[vwes59]

Oh my word - how did I miss this, I can see the reason for the 2nd main switch !! See photograph below. I'm right the far right MS2100 switch is connected the wrong way round, and the tails are then connected in reverse to the middle main switch to correct the polarity, which is why I didn't pick it up. You can just see at the top of the MEM switch the Neutral is in the Line and the Line is in the Neutral

 

[Zerax]

My preference... in order... would be;
1. Replace tails
2. Through crimps, properly made and heat shrinked... you'll best off using decent hydraulic crimpers for that with that size cable.
3. Henley type connector block... I think there's a Proteus one that might work

 

[UNG]

Oh my word - how did I miss this, I can see the reason for the 2nd main switch !! See photograph below. I'm right the far right MS2100 switch is connected the wrong way round, and the tails are then connected in reverse to the middle main switch to correct the polarity, which is why I didn't pick it up. You can just see at the top of the MEM switch the Neutral is in the Line and the Line is in the Neutral

Not quite sure where you are seeing this reverse polarity other than the tabs on the switch

That main switch in the middle looks like a replacement for a failed RCD or to solve an RCD tripping problem due to a lack of testing and a fault being present

 

[vwes59]

Found what this board SHOULD look like. I'm just wondering if I should just get one of these, rip the inards out of both, and put the inards of this one into the one in the wall, and not faff about trying to rewire or understand the mess.

 

[westward10]

That is probably a good idea as who knows how the existing parts have been doctored.

 

[timhoward]

Oh my word - how did I miss this, I can see the reason for the 2nd main switch !! See photograph below. I'm right the far right MS2100 switch is connected the wrong way round, and the tails are then connected in reverse to the middle main switch to correct the polarity, which is why I didn't pick it up. You can just see at the top of the MEM switch the Neutral is in the Line and the Line is in the Neutral

I don't think there is a right/wrong for far right switch, other than how the manufacturer intended it's installation in that CU.
The middle switch had to be connected that way around as presumably the bus bar has a leg in the Line at the bottom and needs to extend to the right.
So I don't think anything has incorrect polarity in practise, other than the markings being backwards on the middle switch.

Found what this board SHOULD look like. I'm just wondering if I should just get one of these, rip the inards out of both, and put the inards of this one into the one in the wall, and not faff about trying to rewire or understand the mess.

Sounds like a plan, but I'd IR test each circuit first, L+N to earth to find any potential issues when circuits become RCD protected again..

 

[brianmoooore]

My solution to this would be to leave the RH main switch exactly as it is, remove everything else and fit a full house of RCBOs.
I'm not familiar with Niglon CUs, but as long as the switch out terminal and the MCB/RCBO in terminals line up, a new busbar an be fitted.
Any original polarity markings on the main switch should be erased, as it's now reversed as to what is was originally.
This solution is relatively simple, doesn't disturb the décor, provides an upgrade to the protection, and imposes a sufficient financial penalty on the householders to dissuade them from employing bodgers again.

 

[Strima]

My solution to this would be to leave the RH main switch exactly as it is, remove everything else and fit a full house of RCBOs.

^^this^^

But the Eaton MS in the middle has me wondering if there's a fault causing the RCD to trip and this was his/her bodge to get round it.

 

[brianmoooore]

^^this^^

But the Eaton MS in the middle has me wondering if there's a fault causing the RCD to trip and this was his/her bodge to get round it.

That's one of the reasons I suggested RCBOs. It will be easier for the consumer to comprehend if, for instance, a socket circuit trips out, that it's their washing machine causing it. None of this "why don't my lights work if the washing machine is duff?"

 

[Strima]

That's one of the reasons I suggested RCBOs. It will be easier for the consumer to comprehend if, for instance, a socket circuit trips out, that it's their washing machine causing it. None of this "why don't my lights work if the washing machine is duff?"

I don't even fit split load boards anymore, they're so last year... ?

 

[Dartlec]

Found what this board SHOULD look like. I'm just wondering if I should just get one of these, rip the inards out of both, and put the inards of this one into the one in the wall, and not faff about trying to rewire or understand the mess.

Is that an official 'publicity' shot? If so and that's the best they could get things to fit then that's not a great advertisement - worse than the MK lean!

Might well be the best way to resolve what's there given the limitations of replacing it... Though some RCBOs for at least some circuits sounds like a good idea too.

If that's difficult (not sure what their availability of Type A stuff is), then (Tin hat time) - other than perhaps not being able to rely on 16kA breaking current - are there really any risks in replacing it all with another brand of matched switchgear that has been type tested together - I doubt the enclosure it is in makes much difference in terms of safety...

 

[suffolkspark]

Is the second rcd still there somewhere, or has it been binned? Id have no issue with crimping the tails with a hydraulic crimper and heat sleeve, and refitting the second rcd and putting it back to standard, but remember the downstream mcbs shouldn't exceed the rating of the rcd anymore if its got a bigger main fuse in, and really we all ought to be fitting type A rcds too now (can't see what type that one is) personally I'd have the whole thing in the bin and start again.