Maximum load query
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Orb
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Joined: Sat Oct 20, 2007 5:13 pm

Maximum load query

Post by Orb » Sat Oct 20, 2007 5:32 pm

My CU has a 100A isolator and an 80A RCD, my newly installed meter has a 100A label on it. If I wanted to install 2 rings plus a smaller CU on a 45A mcb, plus a cooker circuit and the usual lighting circuit, does that sound like a lot of load on the existing supply? I live in a very old cottage with a 30 year old kitchen/bathroom extension plus a shed/workshop. I am just trying to plan a complete rewire and get a shopping list together before I get my local sparky in. Any comments? Thanks in advance!

BLAKEY1963
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Re: Maximum load query

Post by BLAKEY1963 » Sat Oct 20, 2007 11:30 pm

[quote="Orb"]My CU has a 100A isolator and an 80A RCD, my newly installed meter has a 100A label on it. If I wanted to install 2 rings plus a smaller CU on a 45A mcb, plus a cooker circuit and the usual lighting circuit, does that sound like a lot of load on the existing supply? I live in a very old cottage with a 30 year old kitchen/bathroom extension plus a shed/workshop. I am just trying to plan a complete rewire and get a shopping list together before I get my local sparky in. Any comments? Thanks in advance![/quote]

Orb
your maximum demand is dependant on what is called DIVERSITY .
Which means that the demand is based on not every circuit being
Loaded to full capacity , so not everthing is used at the same time.
There are tables in BS7671 ( 16 th Edition I.E.E , wiring regulations ) , which give diversity values for circuits in different premises.
when u enlist your part p sparky , ask him 2 show u these values in his
reg book.

BLAKEY1963

Orb
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Re: Maximum load query

Post by Orb » Sun Oct 21, 2007 5:27 pm

Blakey - thanks for the info. I have just been looking into diversity today and I understand it now (in a layman's sort of way). Thanks again.

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