Industry News
Home > News/Blog > Industry News > Advantages and Applications of Slip Ring Induction Motors

Advantages and Applications of Slip Ring Induction Motors

Feb. 17, 2022

Advantages and Applications of Slip Ring Induction Motors

A slip-ring induction motor is called an asynchronous motor because it does not run at a speed equal to the synchronous speed of the rotor. The rotor of this motor is wire-wound. It consists of a cylindrical laminated steel core and a semi-enclosed recess at the outer boundary to accommodate a three-phase insulated winding circuit.

Why use slip rings?

Slip difference is defined as the difference between the flux speed and the rotor speed. For a torque producing induction motor, there should be at least some difference between the stator field speed and the rotor speed. This difference is called "slip". A "slip ring" is an electromechanical device that helps transfer power and electrical signals from a stationary to a rotating part.

Slip rings are also known as rotary electrical interfaces, electric rotary joints, rotary rings, or collector rings. Sometimes, depending on the application, slip rings require a higher bandwidth to transmit data. Slip rings improve motor efficiency and performance by improving system operation and eliminating wires hanging from motor connectors.

 Advantages and Applications of Slip Ring Induction Motors

Slip Ring Induction Motor

Benefits of Slip Ring Induction Motors

High starting torque and low starting current.

In the case of slip-ring (wound rotor) induction motors, the speed can be adjusted by inserting a resistor.

High overload capacity of slip-ring motor, smooth acceleration under heavy load and no abnormal heating at startup.

Slip-ring induction motor has the advantages of high efficiency, energy saving, low noise, low vibration, safe and reliable operation, easy installation and maintenance, etc. It can be used for various motors of general purpose, such as ball mill, fan, compressor, pump, crusher, cutting machine, transportation machinery and other original motors. In addition, it can also be used to drive large torque inertia fans, coal mills, rolling mills, winches, electric shovels and other machinery, especially suitable for machinery and equipment under special working conditions with high requirements for motor protection.

Advantages and Applications of Slip Ring Induction Motors

Slip Ring Induction Motors Disadvantages 

Higher initial and maintenance costs compared to squirrel cage motors due to the presence of slip rings, brushes, short circuit devices, etc.

Poor speed regulation when running with external resistors in the rotor circuit

Lower efficiency and power factor of slip-ring motors compared to squirrel-cage induction motors

Lower power factor at light loads

Sensitivity to supply voltage fluctuations

Advantages and Applications of Slip Ring Induction Motors

Heavy Duty High Voltage Slip Ring Motor

Slip Ring Induction Motors Applications

Induction motors typically have a lower starting torque than DC series motors Slip-ring induction motors have the huge advantage of high starting torque compared to squirrel-cage motors. Therefore, slip-ring induction motors are typically used where loads require high starting torque or good speed control. They are used in cranes, hoists, compressors, printing presses, large ventilation fans, and loads requiring speed control, such as for driving lifts and pumps.

(1) Greater starting torque than squirrel cage rotor motors is required.

(2) Insufficient feeder capacity to start squirrel cage rotor motors.

(3) Need for a small range of speed regulation.

(4) "Electric shaft" synchronous drive. Such as compressors, sugar mills, textile machines, winches, wire drawing machines, conveyors and other machinery.

ZCL GROUP is a modern import and export company that manages electrical equipment, mechanical equipment, automation control equipment technology research, technical consultation, etc. With a registered capital of RMB 3 million, With many years of experience in the machinery manufacturing market, it can accurately provide users with demand solutions and help customers solve product technology through professional technical level. Please click the button to contact us.

Advantages and Applications of Slip Ring Induction Motors

Contact Us
  • Tel.: +86 311 8924 6924
  • Email:
  • Fax: +86 311 8924 6924
  • Add.: No.86 Xindian Road, Tianxin District, Changsha City, Hunan, China