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09-18-2012, 10:54 AM   #16
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Quote:
 Originally Posted by electures Rob, I disagree. The motor brach circuit conductors have to be sized at 125% of the motor FLA using Table 430.250. 361 x 125% = 451.25A 700 KCMIL THHN CU (rated 460A) per conductor if three are used. 250 KCMIL THHN CU x 2 per phase if two sets of paralleled (6 conductors in one conduit). 250 KCMIL THHN CU are rated 290A x 2 = 580A x 80% = 464A
You are correct.

In all the motor calculations I've done, this time I failed to include the 125%.

 The Following User Says Thank You to micromind For This Useful Post: electures (09-18-2012)
09-18-2012, 01:05 PM   #17
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Quote:
 Originally Posted by micromind You are correct. In all the motor calculations I've done, this time I failed to include the 125%.
Its okay. No one is perfect. No one.

 The Following User Says Thank You to J. V. For This Useful Post: electures (09-18-2012)
 09-19-2012, 04:10 PM #18 Newbie   Join Date: Sep 2012 Posts: 5 Rewards Points: 10 The compressor has a controller panel with a softstart installed. Does this change any of the parameters?
09-19-2012, 05:01 PM   #19
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Quote:
 Originally Posted by scott.cameron The compressor has a controller panel with a softstart installed. Does this change any of the parameters?
No. All good.

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