VFD on Compressor
VFD on Compressor
(OP)
I have a 60 HP compressor, I don't need such a large compressor, will a VFD reduce the HP? Can I fit a VFD to this thing?
Thanks
-mech
Thanks
-mech
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RE: VFD on Compressor
RE: VFD on Compressor
If it a screw operated in parallel with other machines, you may need to look more closely.
RE: VFD on Compressor
-mech
RE: VFD on Compressor
The concern is whether it would surge - but you would know more than I might about the characteristics.
RE: VFD on Compressor
mech
RE: VFD on Compressor
I've spent 2 days in meetings dealing with a large (30,000 hp) centrifugal natural gas compressor on VFD's & my brain is a little tilted -
Thanks
RE: VFD on Compressor
RE: VFD on Compressor
RE: VFD on Compressor
In reality its the reduction in the amount of work required (cfm, pressure, etc.) that results in the reduced horsepower.
Regards
pennpoint
RE: VFD on Compressor
programed you cannot kill your motor no matter what happens to your power or compressor. Your motor will run much cool-
er and use less power even at 60 hz. The compressor will have to be positively unloaded on start-up with silenoid
valves on both stages. They can be controlled with any vfd. I currently use around 40 hitachi vfds now and they will not die, even after 11 years!
RE: VFD on Compressor
Some darwbacks I presume are,
1. Ineffective lubrication, if the oil pump is connected to crankshaft.
2. Increased vibration due to imbalance at other speeds than designed.
I saw and used good many refrigeration chillers(screw and centrifugals) with variable speed application. I have reservations for using VSDs with screw air compressors. Proper receiver sizing, minimization of leakage and correct usage pressure with compressor on/off(or load/unload atleast) will give better results and at reduced investment.
PS: Power consumption reduces if we reduce mass flowrate through a compressor.
Regards,
RE: VFD on Compressor
RE: VFD on Compressor
"Venditori de oleum-vipera non vigere excordis populi"