Fire Pump Controller (VFD)
Fire Pump Controller (VFD)
(OP)
I have water pumps serving combined water\fire network.
In the Code (NFPA) the fire controller is allowed to start a motor while limiting the current drawn by the motor, the stipulation is that the starting period cannot exceed ten seconds.
My question is there any requirements in the Code which prohibit the use of a Variable Frequency Drive (VFD) as a fire pump controller?
Thanks in advance.
In the Code (NFPA) the fire controller is allowed to start a motor while limiting the current drawn by the motor, the stipulation is that the starting period cannot exceed ten seconds.
My question is there any requirements in the Code which prohibit the use of a Variable Frequency Drive (VFD) as a fire pump controller?
Thanks in advance.






RE: Fire Pump Controller (VFD)
Aside from the added cost, the drive will reduce the overall reliability of the system.
I have never used a reduced-voltage starter on a fire pump and I have seen it only once before.
I would guess that the VFD would have to be part of a tested and labeled fire pump starter assembly and would be required to have a bypass contactor to start the fire pump across the line in the event of a failure of the VFD.
RE: Fire Pump Controller (VFD)
I could have misunderstood all this, but with the restrictions in Article 695, I don’t think anyone could produce an NFPA 20-listed controller with a VFD.
RE: Fire Pump Controller (VFD)
busbar, the only restriction I see in the NEC is that VFD should be listed for fire service which I’m not sure if it is available, other requirements could be met.
RE: Fire Pump Controller (VFD)
This would allow you to use the VFD for normal operation and still have a UL-listed fire pump controller for emergency service.
I don't know if this would be acceptable to local inspectors, or more importantly, your underwriter, but it get you a lot closer to a standard system.
dpc
RE: Fire Pump Controller (VFD)
RE: Fire Pump Controller (VFD)
RE: Fire Pump Controller (VFD)
I hate to say it, but no one will give you much credit for being creative when it comes to fire protection system.
It might be less costly in the long run just to take the conservative brute-force approach.
You have to pick your fights, and you won't win any with a fire marshall.