A transformer is not a solution, due to size constraints, but we do have 240V motors as well, so we could use them and forget about PWM stuff. But if we could make that work, we could reduce the number of motors referenced in our warehouse...
Thanks for the support
Well, basically, the motor is actuating over a big contactor, and the maximun cycle is limited to that one, in order to avoid overstress on the contactor.
Yep, 340VDC, but...we are not filtering the supply, so we get an average value of 240V. I know about rattling risks and so on, but the motor will only work 2 secs every ten minutes. Our final customer decided not to filter the supply so....
Sreid, field voltage is applied in a 50% duty cycle as well, same as the armature voltage, so they are "syncronized". Apparently, it worked, but we have to do more tests (measure speed and torque, and current) yet.
I have a "rule of thumb" when dealing with tracks isolation. DIL-6 packages of some optocouplers are certified for 5KVrms isolation (under certain condicitons of humidity), and the pitch between isolated pins is 7.62mm. Therefore, 7.62mm must be enough for 5KV track isolation.
Hi,
We are studying the possibility of supplying with a 240V (mains) PWM signal, 50% duty cycle, a 120V/450W DC shunt motor. We are not experts on this area, so we are concerned about the possible damage that overvoltaging may cause in the windings.
Could anybody confirm if this approach will...
