Our motor use separately-powered fan for cooling beacause it could have variable speed and It is working well too.
The motor is running at a steady rate and it is designed to use with the VFD.
Actually, we are doing the vibration analysis every month and it is ok.
Thank for your response,
The speed from the name plate is 1.500 rpm with 8 pole 50hz.
The speed of the motor could be 800 or 100 rpm depend on process.
Both motor have PTC thermistor already installed in them and they are working well.
About the PTC should have shut down the VFD, your are...
Thank you for your response, THe speed of the motor is 1500 rpm, so It is working at the nominal speed and it has external fun.
THe motor is working since 2011 without the issues.....
However, we see the currect of the three wire is the same but a wire has 3 C degree more tha other wires.
Also...
HI, we have a extruder, it has a motor 400HP with the Altivar 71 VFD.
THe original motor was burn and we rewind it, but it has overheating 100C, torque at 80% and the current is 400 amp, it is low beacause support 590 amp.
So that, we buy a new motor and it has the same issues...
