tap rule

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frostback

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gentlemen,can someone please help with this code question.
I have an existing 400a fusible switch presently serving a 100 kvar
capacitor(its the only available switch in a multiple main swbd)
Can i relocate the capacitor adjacent to the existing location which i now will use as a tap box, and in addition extend the feeder from the tap box to a 225kva 480/120/208v transformer a distance away.If i use 400a wire
throughout and fuse the switch at 400a do i or dont i need secondary
disconnect switches (200a for the capacitor and 400a for the 225kva xfmr)
 
Re: tap rule

frostback said:
gentlemen,can someone please help with this code question.
I have an existing 400a fusible switch presently serving a 100 kvar
capacitor(its the only available switch in a multiple main swbd)
Can i relocate the capacitor adjacent to the existing location which i now will use as a tap box, and in addition extend the feeder from the tap box to a 225kva 480/120/208v transformer a distance away.If i use 400a wire
throughout and fuse the switch at 400a do i or dont i need secondary
disconnect switches (200a for the capacitor and 400a for the 225kva xfmr)
Click to expand...

your total load is over 400A at 460V if the xfmr is fully loaded.
 
So will the transformer and the capacitor be on the load side of the 400 amp disco with 400 amp rated conductors?
 
The 225 kva xfmr is serving a 600a 120/208v meter center with
(6) 100a meter /bkr units with a total calc load of 200 kva .The 100 kva
capacitor draws 120a according to the literature, total load of 360 amps.
Yes the capacitor and the 225kva xfmr are on the load side of the
existing 400a switch with new 400a fuses and 500 mcm cu wire throughout
 
If i am limited to 125 % of the primary of the xfmr i would need to have a
separate 400a switch fused at 350a and similar for the capacitor limited to 135% of the rated current requiring a 200a switch fused at 150a.
Did i just answer my own question?
 
frostback said:
The 225 kva xfmr is serving a 600a 120/208v meter center with
(6) 100a meter /bkr units with a total calc load of 200 kva .The 100 kva
capacitor draws 120a according to the literature, total load of 360 amps.
Yes the capacitor and the 225kva xfmr are on the load side of the
existing 400a switch with new 400a fuses and 500 mcm cu wire throughout
Click to expand...

oops. must have been a slip of my calculator finger. i get 125a for the capacitor.
 
"with a total calc load of 200 kva .The 100 kva
capacitor draws 120a according to the literature, total load of 360 amps."

Sure about the math? These two loads are on the same feeder?
 
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