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snerts50

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Sorry for the two in a row

But i was thinking about this one as well.

Why will the current be higher with the additional of the cap?

Shouldn't this LOWER the total current required by the motor, since now the apparent power needed is supplied at the motor rather then over the conductors and therefore through the overload device...

too much thinking, going crazy

with an improved pf and a constant voltage, wouldnt this lower the kVA value of the system and therefore lower the current...

which is then why the overload settings should be reduced...did I just answer my own question? is there a mention in the NEC to size the overload device to the pf and total KVA value...i thought it was simply the FLA value of the motor itself...

am i making sense?

 
Sorry for the two in a row
But i was thinking about this one as well.

Why will the current be higher with the additional of the cap?

Shouldn't this LOWER the total current required by the motor, since now the apparent power needed is supplied at the motor rather then over the conductors and therefore through the overload device...

too much thinking, going crazy

with an improved pf and a constant voltage, wouldnt this lower the kVA value of the system and therefore lower the current...

which is then why the overload settings should be reduced...did I just answer my own question? is there a mention in the NEC to size the overload device to the pf and total KVA value...i thought it was simply the FLA value of the motor itself...

am i making sense?

From the NEC "The rating or setting of the motor overload device shall be based on the improved power factor of the motor circuit.

Adding the cap reduces the KVARS, which causes KVA to drop and also current I*=S/V

 
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