Prior to the advent of the adjustable-speed drive (ASD), the polyphase induction motor operated as a constant-speed motor. Figure 1 shows the well-known torque and current curves versus speed for the ...

What do you check if an HVACR motor is failing to come up to speed or accelerate? Ask yourself the following: Was the motor applied properly? In other words, does it have enough starting or ...

More information: Takanori Harashima et al, Rational engineering of DNA-nanoparticle motor with high speed and processivity ...

This is when the motor never left the start winding and failed to come up to speed. The internal analysis will show the start winding to be discolored from extreme heat prior to its opening. The main ...