Advice on consumer unit replacement.

[Davisonp]

Hi, I have an issue I cannot get my head round.

I have been asked to replace a consumer unit, and the circuits are run in steel conduit with singles for live and neutral and using the conduit as the earth for sockets and lighting. There is also an MICC cable supplying the cooker.

There are two conduit’s entering from the bottom of the CU, and one conduit from the top of the CU along with the MICC entry.

My problem is modern consumer units are taller than the old ones, and I don’t know if it is practice to cut and rethread steel conduit fixed in place and containing cables.

I would consider mounting the new consumer unit in front of the existing unit so the conduit and MICC does not need to be disturbed, but my worry is that once the new consumer unit is in place, the earthing for all circuits is only accessible by dismantling the current consumer unit.

Any Advice?

Regards
Ps Sorry about repeated images, but there is no way to remove an image if added by mistake and no way to reset the add new thread that I can find.

 

[telectrix]

as a suggestion, you could cut the existing CU casing down to about 35mm , leaving the existin back half with the conduits in it as a pattress to screw the new CU on top of. extend the cables with wagos. i'd recommend sa thourough testing esp. of the conduit as cpc.

 

[Davisonp]

as a suggestion, you could cut the existing CU casing down to about 35mm , leaving the existin back half with the conduits in it as a pattress to screw the new CU on top of. extend the cables with wagos. i'd recommend sa thourough testing esp. of the conduit as cpc.

Thank you,
Sounds like a plan although there is still the problem that the actual earthing connections are inaccessible being inside the pattress section.

 

[telectrix]

strap a fly lead from the pattress to the new CU case and to the earth bar.

 

[westward10]

No chance of getting one or two adaptable boxes in there ? Mind you I probably would not want to be undoing that MI gland. They look imperial those conduits, could improve it by fitting serrated washers.

 

[Harwoodandy]

Is there any space either side of the existing CU?

 

[The Ghost]

wow thats quite a challenge

 

[Davisonp]

Is there any space either side of the existing CU?

Not enough space above, below or beside it. I had thought of putting a panel over the front and putting the new unit elsewhere turning this into a junction box.

 

[Davisonp]

No chance of getting one or two adaptable boxes in there ? Mind you I probably would not want to be undoing that MI gland. They look imperial those conduits, could improve it by fitting serrated washers.

I had not even though about imperial fittings. I will defiantly be leaving the existing connections in place. My current though is to use self tapping screws to attach the new CU over the front of the existing CU and supporting it if required.

 

[westward10]

I have seen new boards fitted over old but the existing board is often flush. I would only fit over old one as a last resort, mainly because even though it will be safe it will look terrible.

 

[7029 dave]

deleted

 

[7029 dave]

I had not even though about imperial fittings. I will defiantly be leaving the existing connections in place. My current though is to use self tapping screws to attach the new CU over the front of the existing CU and supporting it if required.

That is not a bad idea, all cable entry's in the back, fly lead an earth from old to new. Shame there is no room at the side.

 

[Jon Barrett]

Hi, I have an issue I cannot get my head round.

I have been asked to replace a consumer unit, and the circuits are run in steel conduit with singles for live and neutral and using the conduit as the earth for sockets and lighting. There is also an MICC cable supplying the cooker.

There are two conduit’s entering from the bottom of the CU, and one conduit from the top of the CU along with the MICC entry.

My problem is modern consumer units are taller than the old ones, and I don’t know if it is practice to cut and rethread steel conduit fixed in place and containing cables.

I would consider mounting the new consumer unit in front of the existing unit so the conduit and MICC does not need to be disturbed, but my worry is that once the new consumer unit is in place, the earthing for all circuits is only accessible by dismantling the current consumer unit.

Any Advice?

Regards
Ps Sorry about repeated images, but there is no way to remove an image if added by mistake and no way to reset the add new thread that I can find.

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Hi, I have an issue I cannot get my head round.

I have been asked to replace a consumer unit, and the circuits are run in steel conduit with singles for live and neutral and using the conduit as the earth for sockets and lighting. There is also an MICC cable supplying the cooker.

There are two conduit’s entering from the bottom of the CU, and one conduit from the top of the CU along with the MICC entry.

My problem is modern consumer units are taller than the old ones, and I don’t know if it is practice to cut and rethread steel conduit fixed in place and containing cables.

I would consider mounting the new consumer unit in front of the existing unit so the conduit and MICC does not need to be disturbed, but my worry is that once the new consumer unit is in place, the earthing for all circuits is only accessible by dismantling the current consumer unit.

Any Advice?

Regards
Ps Sorry about repeated images, but there is no way to remove an image if added by mistake and no way to reset the add new thread that I can find.

View attachment 34021

View attachment 34022

View attachment 34023

View attachment 34024

View attachment 34025

View attachment 34026

View attachment 34027

View attachment 34028

 

[Jon Barrett]

Hello

With the new style metal consumer units it should not be too much of a problem. I see no reason why you can't thread the conduit in situ as long as you are careful. Good luck.

Jon

 

[Pete999]

Hello

With the new style metal consumer units it should not be too much of a problem. I see no reason why you can't thread the conduit in situ as long as you are careful. Good luck.

Jon

Thread the conduit in situ? would like to see how you would go about that.