How to size a contactor for a resistive load??
How to size a contactor for a resistive load??
(OP)
Hello all -
I've got a 40 kW resistive load (heating elements) powered by 480V, 3ph. So FLA = 40kW / (480*sqrt(3)) = 48amps.
I require a contactor for this heating load (ie size 1, 2, 3 etc).
Can someone provide a table or chart that shows contactor sizing based on the resistive load?? I can't seem to find one online or in the NEC. I have the 2011 version of the NEC.
Thanks!! - Phillip
I've got a 40 kW resistive load (heating elements) powered by 480V, 3ph. So FLA = 40kW / (480*sqrt(3)) = 48amps.
I require a contactor for this heating load (ie size 1, 2, 3 etc).
Can someone provide a table or chart that shows contactor sizing based on the resistive load?? I can't seem to find one online or in the NEC. I have the 2011 version of the NEC.
Thanks!! - Phillip






RE: How to size a contactor for a resistive load??
RE: How to size a contactor for a resistive load??
You can read ABB electrical installation handbook, part 2, protection of feeders:
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Milovan Milosevic
RE: How to size a contactor for a resistive load??
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RE: How to size a contactor for a resistive load??
Is there a chart you can link me to online that shows NEMA rated contactors and their associated continuous amp rating?
Thanks
http://politicalplangetis.blogspot.com/
RE: How to size a contactor for a resistive load??
http://www3.sea.siemens.com/step/pdfs/cc_3.pdf