yobbo II - 12-6-2019 at 05:46
Will a Variable Freq Drive work with a universal motor (on a drill). Since universal motors don't care about the frequency they are driven with (will
work on DC) I am inclined to think that you cannot control the speed with a VFD?
I can not find a clear answer on the net.
Device I am looking at:
This device is described as 'universal'.
https://www.ebay.co.uk/itm/Universal-VFD-Frequency-Speed-Con...
Yob
Sulaiman - 12-6-2019 at 06:15
'Universal' motors have their armature winding connected by the commutator electrically in series with the field winding.
A VFD outputs full ac voltage (unless current limited) at variable frequency,
so would not be suitable for controlling the speed of a universal motor.
A simple triac-based phase controller will work
e.g. https://www.ebay.co.uk/itm/10000W-SCR-Voltage-Regulator-Spee...
Fulmen - 12-6-2019 at 06:29
Sulaiman is right.
raffike - 24-6-2019 at 07:04
Vfd will work on three phase and two phase(two windings,one connected thru capacitorI) motors. Simple triac based schemes seems to work fine for
universals.
yobbo II - 24-6-2019 at 15:37
Thanks,
Will purchase triac type. The triac types always instantly get destroyed when used with induction motor. This is what happened my last one.
Yob