Basic VFD questions
Basic VFD questions
(OP)
I'm considering using a VFD to softly engage a lightly loaded system driven by an AC motor. I have a couple basic questions regarding VFD:
1) Can the VFD be set to control motor speed even if the motor is unloaded?
2) After the speed ramp period expires, can the VFD allow full line voltage to the AC motor so that it can produce its full Locked Rotor Torque? (i.e. like a soft starter)
Thanks in advance!
Steve
1) Can the VFD be set to control motor speed even if the motor is unloaded?
2) After the speed ramp period expires, can the VFD allow full line voltage to the AC motor so that it can produce its full Locked Rotor Torque? (i.e. like a soft starter)
Thanks in advance!
Steve





RE: Basic VFD questions
See thread237-282147: Checking a Check List
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Basic VFD questions
RE: Basic VFD questions
Some drives have an inductor between the input rectifiers and the DC bus capacitors to improve the filtering. This would be called a bus choke or DC bus choke. It also improves the input current harmonics somewhat by keeping the rectifier diodes conducting longer.