commercial electrical church calculation

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STEP 1 Use Table 220.3(A) (2005-220.12) and multiply lighting load va to total square footage. Feeder conductor at 125% for continuous load.

STEP 2 Demand load for motel, hospital, warehouse. (Table 220.11) (2005-220.42) All others at 100%.

STEP 3 Compare heat with A/C. Omit smaller. (220.21) (2005-220.60)

STEP 4 Heavy-duty lampholders at 600va each. (220.3(B)(5)) (2005-220.14(E))
Other outlets at 180va each. (220.3(B)(11)) (2005-220.14(I))
Multioutlet assemblies each 5-foot at 180va each. (220.3(B)(8)) (2005-220.14(H))
Show window lighting each linear foot at 200va each. (220.3(B)(7) (2005-220.14(G))

STEP 5 Demand for receptacle loads over 10kva. (220.13) (2005-220.44)

STEP 6 Demand for kitchen equipment. (Table 220.20) (2005-220.56)

STEP 7 Largest motor increased by 25%. (220.14) (2005-220.50)

STEP 8 Size the service by dividing the total va by the applied voltage. Use Table 250.66 to size grounding conductor. (It cannot be smaller than the neutral)
 
One thing to remember about churches that is not in the NEC is that many of them sit there with little load most of the time, but when occupied they often have peak demand conditions, but only for 2 - 4 hours. This is especially true for HVAC guys and determining what size of cooling units to select.
 
kwired said:
One thing to remember about churches that is not in the NEC is that many of them sit there with little load most of the time, but when occupied they often have peak demand conditions, but only for 2 - 4 hours. This is especially true for HVAC guys and determining what size of cooling units to select.
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Often the church will have separate A/C for the sanctuary and assembly rooms from the units for office and classroom portion if they are in the same building. Especially if they are used during the week.
Sized very differently, although they may also oversize the big unit so that it can cool more quickly instead of having to be turned on automatically well in advance of use.
Common practice will vary with climate.
 
This is not in direct response to the OP.

The Steps got me to thinking.

Just a reminder and after the total is found.

The calculation becomes the estimate.

When you compile your esitmate with the comparison used in Step Three; be sure to remember to add back in and account for all the the possible types, sizes, and control wires of the unit not used in your load calc.

Account for all your circuit lengths and proper sizing of each run in the estimate also.

Just stating the obvious but it can add up quick.

There are new designs where the units are now talking to each other and redistributing heat and cooling.
 
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