Old GEC Main cut out

[Jonesy79]

I need to do a job changing a consumer unit in a property which has an ancient GEC mains cut out box. It is a large metal box with a door on the front and a lever at the side which cuts off the power when it is pulled down (and also unclamps the unit door). Inside the door is the main fuse and a couple of connectors at the top where the main tails from the meter are connected to the main tails that go from the cut out box to the c/u - This connection is broken when the lever at the side of the cut-out box is pulled down (the lever controls some 'forks' which are inserted/removed from the connector blocks when the lever is pulled up or down).

I am replacing the old main tails from the cut out box to the c/u which obviously need uprating however, one of the terminal screws in the old GEC cut-out box was cross threaded when the old tails were initially installed and I was unable to remove it without the whole connector breaking (the mains supply comes into the cut-out box, out to the meter, then back into the cut-out box from the meter and out to the c/u)!

Needless to say, its not a type of cut-out box I've worked on before! Would it be possible to get spares for such an old piece of equipment or should I be calling the REC to sort this out? I believe the home owner inquired as to the REC changing the cut-out box completely several years ago (on noticing how ancient it was), but they were uninterested at that time.

Any advice at all on how I can get this issue sorted would be very much appreciated.

 

[bongos]

I wouldn't be opening that up in a hurry myself - it sounds a little delicate at the moment. It's not your job to sort spares/repairs for it anyway.

Advise the customer to ring their DNO to enquire about someone coming out to look at the cutout. Maybe there's a funny burning smell coming from the cutout and the occasional fizzing sound...

 

[holmslaw]

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[ban-all-sheds]

It is - if you read the description it must come between the meter and the CU.

Nowt do do with the DNO, and since Jonesy broke it it's down to Jonesy to replace/repair it.....

 

[Steve]

put a picture up!

 

[bongos]

if you read the description it must come between the meter and the CU.

Yep. Didn't read that properly.

With the main fuse removed I guess it could replaced with a new switchfuse if one is still required.

 

[holmslaw]

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[sparkwright]

Possibly the tails from the meter to the switch fuse could do with replacing too. No doubt they are ancient and undersized.

 

[ccam108]

If you had read the whole post, then it would appear to be a cut-out and isolator 2-in-1.

the mains supply comes into the cut-out box, out to the meter, then back into the cut-out box from the meter and out to the c/u

 

[holmslaw]

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[sparkwright]

put a picture up!

 

[HullMarc]

If you had read the whole post, then it would appear to be a cut-out and isolator 2-in-1.

the mains supply comes into the cut-out box, out to the meter, then back into the cut-out box from the meter and out to the c/u

ccam, as you appear to be on the same wave length as Jonsey79. Perhaps you could do a drawing based on his wonderful description.

Can I have a go?

Of course the material joining the lever & the two forks is non-conductive.

Fused neutral of course.

 

[ban-all-sheds]

Yep. Didn't read that properly.

And I (and a few others) didn't read this properly:

the mains supply comes into the cut-out box, out to the meter, then back into the cut-out box from the meter and out to the c/u)!

Anyway, there's a big switch which turns everything off, and allows a door with no wire seal to be opened which provides access to the incoming supply which is not turned off.

What a good idea.

 

[Jonesy79]

Thanks for the responses. I honestly thought some of the more experienced electricians amongst us would have known what I was talking about immediately but obviously not. I will try and get a picture up in due course.

As Ccam says, its basically a mains cut out and isolator all within one unit, (don't know why I didn't just say that).... After stepping back and thinking about it though its dawned on me that whilst they are part of a single unit, activating the lever that inserts/removes the forks only makes/breaks the connection between the tails that return from the meter, then go out to the c/u - The isolator part of the unit is completely separate from the mains fuse. With this in mind, I'm thinking that if I don't get any joy from the DNO, (which I've got a feeling will be the case), I could simply make the isolator part of the unit redundant and have the tails that return from the meter going into a new separate stand-a-lone isolator, then on to the CU. A modern double pole isolator must be safer than that old fork type anyway. The lever would then only open the door to the unit and give access to the main fuse.

Does anyone see any issues with this course of action (if the DNO doesn't want to know of course)?

NB Holmslaw and some others - I do apologise if my description wasn't up to your standards however, I didn't simply refer to an isolator as a cut out, I referred to the whole unit as a cut out. Although I appreciate that this is still not technically correct, others seemed to get the gist of what I was talking about (the responses even included a remarkably accurate picture). I fully acknowledge that I'm not as experienced as some - I haven't been alive as long as some people have been in the trade. If we were all perfect and knew everything (as I'm sure you do), why would we need a forum like this? I find it pathetic that forum members like yourself (although you are by know means the only one), feel the need to constantly try and undermine others who are seeking to expand their knowledge and experience, (simply because one of their definitions wasn't technically correct). If you have nothing worthwhile to say, don't say anything. If you don't understand something, just accept that even the best of us don't understand some things immediately (or you could have just asked me and I'd have been glad to clarify anything you were struggling with).

 

[holmslaw]

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