taps after generator

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vincedigital

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caribbean
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electrical cad technician
hi,
if i have a 25kw generator and it only has 1 built in circuit breaker. but i need to put 2 circuits to it.
- a fire pump controller with ats
- a 60amp ats for the jockey pump
do i just put a tap box after the generator breaker (by observing 10ft or 25ft tap rule) then just split the tap to the fire pump controller and the 60amp ats?
if yes, is there anything else i have to consider to be code compliant?
if not, if i will replace the tap box with an electrical panel, will i have to size the breaker to the locked rotor current of the fire pump (300amp)?
thanks,
 
You can put a tap box and split the feeder, but are the ampacities of that equipment the same as the set-mounted breaker? You may need a distribution panel to make the protection properly sized. Are both considered Article 700 loads, or is one 700 and the other 701 or 702? 700 loads need to be isolated from 701/702 loads.
 
Also the code would require a UL 2200 listed generator if the pumps are considered 700 or 701 loads, and it is difficult if not impossible to get something that small at 25kW listed
 
ron said:
Also the code would require a UL 2200 listed generator if the pumps are considered 700 or 701 loads, and it is difficult if not impossible to get something that small at 25kW listed
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I feel like a 25kw is going to shut down on overload before the breaker even notices an overcurrent. 300LRA? I had a 25kva portable generator here and it had a 70 amp breaker (which the controller trips at 35a if in 480v mode)
 
ron said:
You can put a tap box and split the feeder, but are the ampacities of that equipment the same as the set-mounted breaker? You may need a distribution panel to make the protection properly sized. Are both considered Article 700 loads, or is one 700 and the other 701 or 702? 700 loads need to be isolated from 701/702 loads.
Click to expand...
i put a 100amp breaker and i think that will suffice with the 46amp (plus 1.25% = 57.5amps) fire pump and a total of 8amps load for the jockey pump ATS load = 65.5amps total
 
I don't think a 25kw generator can start a 10hp fire pump.

Someone else please correct me if I am wrong here, but all the fire pump motors in that size seem to be Code G. So at the upper range of 6.3kva/hp for across the line starting we get 63kva of generator needed to start the fire pump. Need to figure out what the voltage dip will be during starting and what will that do to the ATS for the jockey pump....
 
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