A totally enclosed three phase motor, assembled with a wound slip-ring rotor for very high starting torque. The power options range from 37kW to 300kW.

Product Description


Motor with wound slip-ring rotor for very high starting torque

Totally enclosed, slip ring, wound rotor three-phase asynchronous motors.

Single Speed
  • Power: 37kW to 300kW
  • Frames: 280 to 355mm
  • Voltage: 230Δ/400VÎ¥, 50Hz (other voltages and frequencies on request).

Standard version IP55.

  • Thanks to the insertion of an appropriate rheostat in the rotor circuit, the slip ring, wound rotor motor offers the following possibilities:
  • Adapting the motor torque to that of the driven machine
  • Tolerant of long starts
  • Limits the starting current
  • Sets the speed of rotation with the aid of a permanent slip rheostat (consult our technical department for this application).

The slip ring, wound rotor motor does not depend on the stator being connected in order to start. A rheostat is used in order to start a motor.
Leroy-Somer recommends the liquid resistance rheostat known as the Polystart electrolytic starter.

This type of starter inserts a resistance into the rotor circuit, which gradually reduces until it disappears completely by a short-circuit at the end of the starting period. The technical description « Transient operation – Starters ». Caution, the Polystart is not suitable for hoisting applications.

Use Conditions

In the selection grids the following values are indicated:

  • For a general use in service S3 (FLSB series)
  • For a hoisting and handling S4/S5 (FLSLB series).