load calculation

[tacomafc]

If I was to install a sub panel for 11 air condenser units (geo-thermal). I think I would treat it the same way as you would calculate a feeder for motors. I would total all the F.L.A. and add 25% of the largest motor. Then for example on a 100 amp panel I could only have a load of 80 amp.

 

[iwire]

Then for example on a 100 amp panel I could only have a load of 80 amp.

What do the name plates say?

IMO all you have to do is total the minimum circuit ampacity from all the units that will be the minimum circuit size.

Unless you believe that all of these units will run simultaneously for 3 hours or more you could size the feeder directly to the total MCA for all the units. The MCA already has 125% figured in.

 

[cadpoint]

There's a lot of information in "Article 440", and with a quick skim of it.

I assume your using 440.33 as the bases of your statement ! ?

If you throw in a motor controller keep reading.