Low P.F.
Low P.F.
(OP)
Hi there,
I have a large amout of mixers in my plant with low P.F.
(0.51 @ 100% load ).
There are 50 of them each 20 HP (600 V) and 36.0 A FLA. (High current)
With this P.F. I probably have to double size of transformer.
Or
Is there any way around this? what about capacitor banks?
I need some reference and feedback about them.
Thanks in advance.
Regards,
I have a large amout of mixers in my plant with low P.F.
(0.51 @ 100% load ).
There are 50 of them each 20 HP (600 V) and 36.0 A FLA. (High current)
With this P.F. I probably have to double size of transformer.
Or
Is there any way around this? what about capacitor banks?
I need some reference and feedback about them.
Thanks in advance.
Regards,






RE: Low P.F.
RE: Low P.F.
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Low P.F.
Capacitors as suggested by wareagle is a good idea, but need to check the harmonics.
On the other hand, if those 50 small low PF motors constitue a small percentage of the total plant load, and they don't incur penalty on your utility bills, may be you can just increase the transformer size because I would prefer one equipment less to be maintained in a plant.
RE: Low P.F.
All the replies in this thread are valuable here. I think Digitrex raises the most salient point that if you are meeting the PoCo PF requirement at the supply terminals, then no correction is needed.
RE: Low P.F.
the motor is a Flygt mixer model 4670, here are some information they provide on their website:
Rated Power:14.9kW 20.0 hp
voltage:600 v
Speed (r/min):440
Rated Current: 36.0 A
No load Current: 28.0 A
Locked Rotor Current: 105.0 A
Starting kVA: 109.2
EEMAC CODE : F
Efficiency @ 100% load: 77.5
Efficiency @ 75% load: 76.0
Efficiency @ 50% load: 71.0
Power Factor @ 100% load: 51.0
Power Factor @ 75% load: 43.0
Power Factor @ 50% load: 34.0
Power Factor @ start: 36.0
It would be 50 of them in the plant, at least 25 of them running together.
These are the major loads, although I have a 320A main breaker dewatering unit with some VFDs inside, and a 200 A service for Admin. building and workshop.
Regards,