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Posted By: highground Derating service entrance conductors - 06/02/05 03:32 AM
When installing a multigang meter socket is there deration allowed for the service entrance conductors? Thanks
Posted By: bucketman Re: Derating service entrance conductors - 06/02/05 05:00 AM
I'm trying to think why you would have more than three current carrying conductors in a service enterance.

the only thing I could think of is if it were paralleled.
but still in parallel it's like their the same conductor.
the biggest issuse is busbar of multi meter socket set up is the rating of main busbar feed to all meters you have to watchout the rating i ran into few of that for incomming service cables and out going cables most meter manufacter will list a warning there

Merci, Marc
Posted By: highground Re: Derating service entrance conductors - 06/02/05 12:30 PM
What I meant was, if you have say a four gang setup with 200+200+200+200 amps do the service entrance conductors need to have an ampacity of 800 amps in a residential setting?
Posted By: Celtic Re: Derating service entrance conductors - 06/02/05 01:48 PM
No, the sum of the metering doesn't neccessarrily need to equal the whole of the service.
Annex D ~ Example D4(a) Multifamily Dwelling; Example D4(b) Optional Calculation for Multifamily Dwelling

The Annex refers back to each applicable article,ie T220.10

A two-family home might require a house panel(40A), an 100A panel(1st floor) and a 60A panel (2nd flr) - but the service might be 150A...depending on the calculated load.
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