RichardHebl
New member
I need to calculate the size of a 120/240V 1PH feeder to a panel that will contain the breakers for 3-A/C units: 2-5 Ton (35A min circuit, 50 amp max breaker) and 1-4Ton (24A min circuit, 40 amp max breaker). Can I use the
min circuit ampacity since it is calculated by the full load of the compressor
X 1.25% plus the fan motor? Will a 100 amp feeder be large enough (35+35+ 24 = 94)?
Let me clarify that the branch circuit selection currents of 35A and 24A are taken off the nameplate rating of the A/C unit and I believe are figured using the compressor FLA X 1.25% and then the fan FLA is added to this to come up with the total branch circuit amperage of each unit. My question is not about the disconnects for the units but about the size of the circuit breaker and feeder that will be supplying power to the panel for all 3 A/C units.
min circuit ampacity since it is calculated by the full load of the compressor
X 1.25% plus the fan motor? Will a 100 amp feeder be large enough (35+35+ 24 = 94)?
Let me clarify that the branch circuit selection currents of 35A and 24A are taken off the nameplate rating of the A/C unit and I believe are figured using the compressor FLA X 1.25% and then the fan FLA is added to this to come up with the total branch circuit amperage of each unit. My question is not about the disconnects for the units but about the size of the circuit breaker and feeder that will be supplying power to the panel for all 3 A/C units.
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