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Capacitor conductor sizing

1205 Views 1 Reply 2 Participants Last post by  don_resqcapt19
:001_huh:Needing help with calc for installing a capacitor-

Have a 120/208 1200a MDP that's maxed out for breaker space for a 240v 3 wire 90kvar PF capacitor. The capacitor is a GE GMP50900D333FL. Am looking at tapping the MDP's 1200a buss and feeding a 400a fused switch. The conductor length is about 30'. Question is: Can 350thhn's feed this?

90kvar x .75= 67.5kvar for 208v rating

67.5 x 1000/ 208x1.73= 185.6amps

185.6a x 135% =253amps

350's @75*are 310amps...correct?

can the disconnect be fused at 400a since the capacitor has internal fusing, or do I need to drop the OCP to 300amps?
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How much wire between the bus and the line side of the 400 amp disconnect?
The maximum fuse size for the 350's would be 350 amps.
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