We have a existing 50kVA UPS system, 480 volt, 3 ph, 3 w input, 208/120V, 3ph, 4w output. Existing conduit, input 1"C, 3#4 and output 2"C 4-1/0 & 1#4gnd.
New UPS (with Flywheel system) manufacturers info:
Input 480V, 72Amp, max amp. 90 amp, 3ph, 3w
Output 208/120, 50kVA, peak amp. 218 amp, 3ph, 4w
I suggest use: input - 1 1/4"conduit, 3#3 w/#8gnd
Output - Since maximum output is 50kVA, maximum load is 139 amp, 1.25 times is 174 amp. So use 4#2 and #6gnd. in exsiting 2" conduit.
Output wires terminate into an existing 225 amp , 208/120 panel.
Note: Output wire sizing will be coordinated w/manufacturer.
Existing acutal load on UPS sytem is no more than 25kVA. No additional load is anticipated.
Additional major load additions will have to be cleared w/engineering staff.
New UPS (with Flywheel system) manufacturers info:
Input 480V, 72Amp, max amp. 90 amp, 3ph, 3w
Output 208/120, 50kVA, peak amp. 218 amp, 3ph, 4w
I suggest use: input - 1 1/4"conduit, 3#3 w/#8gnd
Output - Since maximum output is 50kVA, maximum load is 139 amp, 1.25 times is 174 amp. So use 4#2 and #6gnd. in exsiting 2" conduit.
Output wires terminate into an existing 225 amp , 208/120 panel.
Note: Output wire sizing will be coordinated w/manufacturer.
Existing acutal load on UPS sytem is no more than 25kVA. No additional load is anticipated.
Additional major load additions will have to be cleared w/engineering staff.
