Reccomend me a CU please

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The joys of living in the Highlands. I am trying to find a solution to a job 80 miles away, without making a 160 mile round trip to look at the job. I have lots of photos and emails from the customer.

It started out as "fix the burned out neutral bar" in one CU, and move the other CU to a new location.

I could replace the burned out neutral bar ( I have a spare) but told them I can't move the old CU, it needs a new one (no areseedee etc)

The logical thing would therefore be one new larger CU to replace the two existing ones.

BUT

Here's the loads:

12KW electric boiler presently on a C50

Immersion B16

smokes B6

Cooker B50

Shoiwer B40

Sockets B32

Sockets B16

Water Heater B40    *

Unknown B40    *

Lights B15      *

Unknown B32    *

It's the little Proteus CU with the C50 that has the burned out neutral bar.

But on the main CU it's the last 4 that worry me. B40A water heater? WTGrape is that?  Lights on a B15? and what's the unknown circuits on a B40 and a B32

Clearly this can't all be settled without a visit to determine the unknowns.

Anyway what I want to do is go armed with a suitable CU and work out all the unknowns when I am there.

So given the big loads, particularly the C50 12KW boiler, a big shower, a big cooker and a few unknowns, what I am really asking is does anyone know a CU that will cope with such big loads without the neutral bar melting and being back to square 1?  I guess this shows a lack of confidence in any of the rubbish that's churned out these days.

Part of me says fix the burned out neutral in the Proteus and leave that for the boiler and fit a smaller CU for the other stuff, just so reduce the loading on the new CU.

 
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Eaton .   

Is the neutral bar not a loose connection do you think?

Nothing wrong with Control Gear  either .

The existing has the look of someone just shoving any size breaker in  TBH .

 
What about a three phase board converted to single phase?? At least it will give you a bit of room to work in there and a decent sturdy board should be easy to get??

john..


i was thinking the same. then you can spread the load across all 3, but you still have the problem of the neutral, although its more likely to have a higher rating than a domestic CU

 
Re the burned out neutral bar. Again I have not been to look, but the customer says all the screws are tight.

Do the likes of Control Gear or Eaton have twin screw neutral bars?

I guess my biggest concern is the neutral bar giving up again, even if properly tightened, due to the fact I don't believe any of the normal MK, Wylex, Craptree etc are any good in that respect, and I don't want to have to go and fix it because nobody makes a properly engineered CU these days (they just stick the same rubbish in a tin box so it won't burn the house down)

Not enough space for a 3 phase board.

I think you are right about "any old MCB will do" in the main CU. It's not helped by the customer knowing nothing (they started off telling me the burned out CU only fed the smokes and an immersion heater, until I got them to take a photo and give me the model number from which I determined it's a 12KW electric boiler)

 

 
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As you are looking at the 50A load, you need to look @ Acti9, not Resi9, or Easy 9.

Search Acti9, it's the old MG board, they are basically 1ph 3ph boards if that makes sense.

 
It would be handy if you could install a relay so the shower wont work if the 12KW boiler is pulling FLC but probably wont be a viable option.

 
There may not be space for an Acti9. It's above a door and window already, so only space for a small domestic sized CU. An Easy9 would fit but are you saying that's the same carp as any other domestic CU?

What's the height of a 12 way Acti9 type A?
 

 
Agree with Rob, but, leesparkykent, you could do this relatively easily with Acti9.
yeah I meant installing a cable between shower isolator and relay. Then cable from boiler/wiring centre to relay so the boiler control signal can be taken through the normally closed contact. Getting the cables in position might not be an option.

 
There may not be space for an Acti9. It's above a door and window already, so only space for a small domestic sized CU. An Easy9 would fit but are you saying that's the same carp as any other domestic CU?

What's the height of a 12 way Acti9 type A?
 


Yes, easy 9 is a rebranded version of another company schneider took over.

Acti 9 was the Merlin Gerin range, not sure if easy 9 were square d?

 
There may not be space for an Acti9. It's above a door and window already, so only space for a small domestic sized CU. An Easy9 would fit but are you saying that's the same carp as any other domestic CU?

What's the height of a 12 way Acti9 type A?
 
300 high up to 18 way

yeah I meant installing a cable between shower isolator and relay. Then cable from boiler/wiring centre to relay so the boiler control signal can be taken through the normally closed contact. Getting the cables in position might not be an option.


Just use current sensors locally.

Acti9

http://download.schneider-electric.com/files?p_enDocType=Catalog&p_File_Id=1530259451&p_File_Name=SE8863+Complete+.pdf&p_Reference=SE8863

 
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300 high up to 18 way
Thanks. I have asked the customer to measure the height available.

If it will fit, and the customer can stomach the higher cost, then it looks a good solution.

In fact if the customer can't stomach the cost then I will probably decline to quote for the job.

 

 
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