Ciruit protection for fire pump

[anbm]

If fire ATS/controller was fed out of two power sources (normal utility and emergency generator) as allowed 695.B(2).

On normal source (utility power) the circuit protection shall be sized for locked motor current start ( or 6 X FLA )

On mergency source (gererator) the circuit protection shall be sized for regular motor start ( or 2.5 X FLA )


Is this correct? Just want to confirm, I am on the road now. Thanks!

 

[bob]

If fire ATS/controller was fed out of two power sources (normal utility and emergency generator) as allowed 695.B(2).

On normal source (utility power) the circuit protection shall be sized for locked motor current start ( or 6 X FLA )

On emergency source (gererator) the circuit protection shall be sized for regular motor start ( or 2.5 X FLA )


Is this correct? Just want to confirm, I am on the road now. Thanks!

You have it reversed.
On normal source (utility power) the circuit protection shall be sized for regular motor start ( or 2.5 X FLA )

On emergency source (gererator)the circuit protection shall be sized for locked motor current ( or 6 X FLA )
You don't want the pump to stop regardless of the load on the pump motor. It should run til it fails. No need to protect the motor when the place is on fire.

 

[anbm]

Got the code now, here it is:

695.4.B(3)...overcurrent protection devices between an on-site stanby generator and a fire pump controller shall be selected and sized in according to 430.62 to provide short circuit protection only....

(1) Overcurrent Devices Selection. The overcurrent protective device(s) shall be selected or set to carry indefinitely the sum of the locked-rotor current of the fire pump motor(s) and the pressure maintenaince pump motor(s) and the full load current of the associated fire pump accessory equipment when connected to this power supply. The next standard overcurrent device shall be used in accordance with 240.6. The requirement to carry the locked-rotor currents indefinitely shall not apply to the conductors or devices other than overcurrent devices in the fire pump motor circuit(s).