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feeder sizing to demand?

feeder sizing to demand?

feeder sizing to demand?

(OP)
I am in need of a clarification so...

If I use the demand load for things like kitchen equipment and receptacles do I get to use those discounts in sizing my feeders?  or do I have to use 100% as in connected load when sizing the feeder? what about breaker sizing?

Thanks for any light that can be shed on this.

RE: feeder sizing to demand?

Jself, In the electric utility, when we receive requests to serves, such as for housing developements, I will often add up the connected load, then divide this by a diversity factor of 40 - 60% depending on the type of load (industrial, residential..).  If you are talking specifically house wiring and breakers, then I believe you need to follow the National Electric Code which will often make you allow for 200% overload or so.  You may want to review the NEC if this this is what you are referring to.

RE: feeder sizing to demand?

If these demands are specified in NEC code article 220.10 "general" follow it's statement, but alway check with your local building department first.

Good luck

RE: feeder sizing to demand?

You must use the rules in section 220. There are tables
that give you any adjustments necessary. Table 220.3A,
220.11, 220.18, 220.19and 220.20. 220.30 allows an optional
caculation using the rules of the section.
The utility rules do not apply to your caculations.

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