YRKK is a wound-rotor high-voltage motor: the rotor winding is brought out through slip rings, so a liquid resistance starter can raise the starting torque while keeping the starting current low. That is the combination required by ball mills, crushers, belt conveyors, kiln drives and induced-draft fans, where a squirrel-cage motor of the same rating would demand a starting current the plant transformer cannot supply.
Frames run from YRKK500 to YRKK800 across 220 to 2,500 kW at 6 kV or 10 kV, four to twelve poles. Cooling is IC611 air-to-air as standard, with IC81W air-to-water where the motor sits in a hot or dusty house. Bearings are sleeve type on the larger frames and roller on the smaller ones, with PT100 sensors in the windings and bearings wired to a terminal box for the plant DCS.
Sizing is done against the driven machine, not the motor alone: starting torque, starting time, flywheel moment, starts per hour and the starter type all change the selection. Send us the driven equipment, the required torque curve and the supply voltage, and we will confirm the frame, the rotor winding and the starter setting. Each unit is routine-tested with no-load current, winding resistance and vibration recorded before dispatch.
- 220 to 2,500 kW, 6 kV / 10 kV, 4 to 12 poles
- High starting torque with low starting current when paired with a liquid resistance starter
- IC611 air-to-air or IC81W air-to-water cooling, IP54 / IP55
- Slip ring and brush gear accessible for maintenance; brush lifting device optional
- PT100 in windings and bearings, space heaters, vibration sensors on request
Lead time is 60-90 days depending on frame and winding, with the starter quoted separately if required. Spare brushes, slip rings and bearing sets are supplied against the motor serial number.
