DC Motors: Overview
Power supply | DC | Battery supply possible |
---|---|---|
Driver electronics need | No | |
Speed accuracy | Low |
Effected by load torque |
Speed control | Voltage ↕ | Open loop or closed loop speed control Closed loop – high accuracy, but sensor need |
Position control | High effort | Closed loop position control and sensor need |
Overloadablity / load inertia | High |
High start torque or peak load torque |
Lifetime | Low | 200…2000 h (limited by wear of brushes) Depend on speed, current and brush config. |
Speed range [rpm] | 1500...30000 | No load speed |
Efficiency | 65...80% | At 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 Braking (dynamic only) by winding short circuit |
JE Brand |