SPYDERLK
Super Star Member
- Joined
- Feb 28, 2006
- Messages
- 10,360
- Location
- VA
- Tractor
- JD2010, Kubota3450,2550, Mahindra 7520 w FEL w Skid Steer QC w/Tilt Tatch, & BH, BX1500
I believe the motors used in winches are series wound/universal style. What this means is that the armature and field coils are in series and always have the same current, but the drive voltage splits between them. ... Va + Vf = 12 if you will. When the motor is stalled or at low speed this is probably a pretty even split and the current is very high. The field is strong due this high current and a lot of torque is avaiable. But as speed increases the armature generates a backward acting voltage that uses more and more of the 12 supply volts so current goes way down. Due to the resulting weak field the motor will go very fast and produce very little torque. Permanent magnet motors dont have this problem because the field stays strong. Internally rewiring a universal motor to separate armature and field is probably the best bet if youre able to deal with it. Feed full voltage to the armature and vary the field supply voltage [and therefore its current] to control speed. A very strong field will limit the speed and give very high torque. You may also have to lower armature voltage. A pot will work for the field but not the armature cuz armature Va would drop like a stone under load and yould get poor torque. If you want a simple solution a suitable 12V PM motor will do it. I doubt cheap. :confused3:
larry
larry
