Calc for @800amp panel

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bill@usps06492

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Connecticut
I have an 800amp 120/208 panel that feeds 4 individual sorting machines,each with a 70 amp flc. All are 3phase 120/208 5wire . The ocpd is set at 125 amp, which is roughly 175% of the 70a flc, and the indiviual feeders are 2/0 copper. I want to know how I can figure out how many more pieces of the same equipment I can install off of this panel without overloading it? The XF that feeds this panel is 300kva, 480v on the primary 3phase. it's ocpd is set at 500amp.
What I would like to do is to have a total of 9 pieces of equipment fed from this panel, the 4 existing, and 5 new machines. All will have a flc of 70amps @ 120/208v 3 phase. This equipment is run at different intervals on each shift, 24 hours per day, but the machines are never ran for more than 3 hours straight.
9 x 125 ocpd / 1.73=650a 800a x 80%=640a 9 x 70flc / 1.73=364a
Any information you can pass my way would be great. Thanks Bill
 
See 430.24. Assuming 70 FLA is one motor (for ease and unknown) 70*1.25=87.5 amps. 800 amps - 87.5 amps = 712.5 amps / 70 amps = 10.18. 10 units plus one unit equals 11 units max. Of course other items such as use, starting them all at once, etc., comes into play also and might adjust that number down on a practical basis. Remember, the code is a minimum.
 
The sorting machines are made up of a series of individual units refered to as "stackers", and these stackers have a 3phase 1.5hp motor (1.5hp per table 430.250 flc is 6.6a @ 208v) that drives the belts and pulleys in the stacker unit. On each machine there is a name plate that gives the flc based on how many stacker units the sorter is made up of. I'm dealing with 13 stacker sorters, and the name plate on it states it has an flc of 70a @208v. Thats somewhere between a 20-25hp motor @208v. Also when the sorter starts all the motors start at the same time, but all the individual sorters do not start at the same time.
Bill
 
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