Motor starting by reactor
Motor starting by reactor
(OP)
I have a motor , which is designed on 80% reactor starting.
Can I set the starter with 65% tap to start this motor
Can I set the starter with 65% tap to start this motor
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Motor starting by reactor
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RE: Motor starting by reactor
Torque varies with the square of the voltage.
RE: Motor starting by reactor
So, with 65% tap reactor starter, the starting torques is smaller, the starting time will be longer. Am I correct?
Motor manufacturer torqe vs. speed characteric curve, it nly show 100%, and 80%. So, this motor still can be started at 65% or 75% with longer starting time.
RE: Motor starting by reactor
RE: Motor starting by reactor
As edison said, you have to consider the torque requirements of the driven equipment, not just the motor. If this is a centrifugal pump starting with discharge valve closed, or a fan starting with dampers closed, the starting torque requirements are generally low enough to allow starting at a reduced voltage. The acceleration will take longer.
If you are trying to start a high-inertia load, it could be a problem, since the starting and accelerating torque requirements will be higher.
RE: Motor starting by reactor
I have seen lots of motor curves giving 100% and 80% voltage characteristics. Have we started any of those motors at 80% voltage? No.
I also think you mean autotransformer starting. A reactor starter does not apply a fixed voltage level to the motor. The voltage varies inversely with the starting current.
As the others have posted - you need to determine if using 65% voltage will allow the motor to accelerate close to full speed.
RE: Motor starting by reactor