OptionalMultiFamilyService

Optional Multi Family Service Calculations

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This calculation is the workhorse for all multi-family dwelling units. NEC 220.84 gives the technique repeated here:

Determine the total connected load then multiply by the demand factor as given in table 220.84

Total connected load is computed as follows:

1. 3va per square foot.
2. 1500va for each small appliance circuit and each laundry circuit.
3.nameplate of everything else except heat and ac.
4. larger of heat or ac.

Multiply this total by the demand factor from the table mentioned above.

Divide by voltage of the service and divide by 1.732 if the service is to be three phase.

That's it. You're done.

It's so simple I don't have practice problems for this calculation.

 

 

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