480 VAC 200 Amp Load Center Capacity

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willie2014

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I have a 480 V 200A load center which is supplying 9 277V 20A circuits, 1 480V 20A circuit, 1 480V 25A circuit, and 1 480V 125A circuit for transformer for 120/240V load center.
Question: Will this load center support 3 more 480V 40A circuits?
 
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GoldDigger

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That question cannot be answered without knowing the actual load on each of the existing circuits and the new circuits.
Are all of the circuits you list single phase?
(Either line to neutral or line to line)
If they are all single phase and are arranged to balance the load optimally you may be OK.
 
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charlie b

charlie b

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Your question is similar to saying that you still have 6 unused checks in your checkbook, and asking if you still have enough money to buy a new TV. The ratings of the various breakers can give you a notion about the highest amount of load your panel might have connected to it. But the actual load is almost certainly much smaller than the sum of the breakers. For example, you might have 4 light fixtures powered by a 20 amp circuit, with each light having a single 60 watt bulb. The total load on the 20 amp circuit would be only 2 amps. So the presence of a 20 amp breaker really does not tell you how much of the panel's available capacity is being used by that circuit.

Welcome to the forum.
 
bob

bob

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Alabama
Thats not a good method. You need to inventory the load and calculate the load by the NEC rules or make an actual measurement of the amperage. The panel can handle 400 amps if the load is not continuous.
 
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GoldDigger

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bob said:
Thats not a good method. You need to inventory the load and calculate the load by the NEC rules or make an actual measurement of the amperage. The panel can handle 400 amps if the load is not continuous.
Click to expand...
Why can a 200A three phase panel handle 400A?
 
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