If I understand how to size wire and overcurrent protection if 1 circuit contains only motors. But what if it contains other loads like a heater for example.
Suppose I have one 25HP motor (74.8A FLC), one 10HP motor (30.8 FLC) and one 5kW heater (13.9A). All loads are continuous at 208V 3phase.
minimum wire size would be:
74.8(1.25) +30.8 + 13.9(1.25) = 141.7 amps -> 1/0 copper
Fuse size would be:
74.8(1.75) + 30.8 + 13.9(1.25) = 179amp ->175 amp fuse?
Since a heater is associated with the circuit, can we use 1/0 copper for the circuit or must it be 2/0?
is the calculation correct?
Suppose I have one 25HP motor (74.8A FLC), one 10HP motor (30.8 FLC) and one 5kW heater (13.9A). All loads are continuous at 208V 3phase.
minimum wire size would be:
74.8(1.25) +30.8 + 13.9(1.25) = 141.7 amps -> 1/0 copper
Fuse size would be:
74.8(1.75) + 30.8 + 13.9(1.25) = 179amp ->175 amp fuse?
Since a heater is associated with the circuit, can we use 1/0 copper for the circuit or must it be 2/0?
is the calculation correct?
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