Rotacon is an automatic rotor controller designed for use with large kW slip ring motors. it is based on the principle of a liquid electrolytic resistance varied by moving electrodes.
It ensures smooth acceleration and can meet specific requirements of starting torque and speed control by slip regulation.
In standard version the range can be up to 20,000 kW in five frame sizes and up to maximum rotor voltage of 3,500 V between slip rings. Versions can be made available to suit non - standard or specific customer requirements.

DESCRIPTION
Electrolyte Tank
It is made of heavy duty sheet steel to contain liquid electrolyte to form the electrolytic resistance. Anti-evaporation oil seals the electrolyte surface to minimise evaporation and prevent deterioration of the electrolyte .

Electrode Assemblies
Three assemblies are mounted in a row. Each comprises of one moving and one fixed electrode, contained in a polypropylene shroud to ensure sufficient isolation between phases or to minimise cross currents or fly effect..

The nickel plated steel electrodes consists of concentric cylinders which, in the "minimum resistance" position, merge without touching each other to give a high maximum resistance ratio as shown in the above (curve).

The moving electrode travels vertically inside the shroud, guided by a polypropylene slide.

SPECIAL APPLICATIONS
Control System
The displacement of the electrode carrier is controlled by a worm drive operated by a pilot motor. A clutch is provided for manual operation.
Standard starting times are 20, 30, 40, 60, 80 or 130 seconds and are pre-set at works.
Limit switches are used to control the operation of the pilot motor and also to energise the contractor which short circuits the residual resistance at the end of run-up time.
Thermal overload protection can be provided for the pilot motor.
An electrical interlook prevents re-starting before the moving electrodes have returned to their starting position.


Switchgear Panel
It incorporates all the necessary switchgear and controls in IP 54 execution with an undrilled gland plate at he bottom of cable entry.
Stator interlocks and other specific control requirements can be provided.

Optional
-Electrolyte forced circulation.
-Increased heat dissipation, by means of a heat exchanger for Short duty cycles.

DUAL MOTOR STARTING

SLIP REGULATION  OR VARIABLE SPEED

UNIT FOR SYNCHRONOUS INDUCTION MOTORS