Universal Motors: Overview
Power supply | AC or DC | Mainly AC, direct connection to mains |
---|---|---|
Driver electronics need | No | |
Speed accuracy | Low | Effected by load torque Manufacture tol +-10% of no load speed |
Speed control | Voltage ↕ | Open loop speed control |
Position control | High effort | Closed loop position control and sensor need |
Overloadablity / load inertia | High | Very high start torque or peak load torque Able to accelerate high load inertia |
Lifetime | Low | 300…2000 h (limited by wear of brushes) Depends on speed, current and brush config. |
Speed range [rpm] | 10000…50000 | No load speed |
Efficiency | 60…80% | Operating point of max.efficiency |
Power vs. size | High | |
Winding thermal protection | Need | If overload (mechan.blocking) not excluded - Current limitation or thermal contacts |
Load sensing | Easy | Current rises with load |
Stalling permissible | No | No or only short time (winding overheat) |
Electromag.interference EMI | Critical | Suppression means (capacitors / varistors) |
Braking/Holding torque | Low | Detent torque (when power switched off) |
JE brand |