JR Series Wound Rotor Slip Ring Motor

JR series motor is wound rotor three-phase asynchronous motor. It meet the standard of JB 564-64 technical requirements. JR series must insert starting rheostat in rotor circuit in advance, and can’t be started directly by short circuiting the rotor winding. The basic mounting mode of this type is horizontal installation with bottom foot. It should be connected with the driven machine by coupler device. JR motor adopted a double – sided radial ventilation system and antifriction bearing. By the side of shaft extension end, the outlet box is on the right of the frame. It can be reduced power running for long time in condition of reduce the torque.

The series JR guarantees, at rated voltage, the ration of the maximum torque to rated torque not less than 1.8.

A starting rheostat must be connected into the rotor circuit in advance before the series JR is started, the starting mode based on short direct connection to rotor windings may not be allowed.

What is a Slip Ring Induction Motor?

Definition: A slip ring induction motor is referred to as an asynchronous motor as the speed at which it operates is not equal to the synchronous speed of a rotor. The rotor of this type of motor is wound type. It comprises of a cylindrical laminated steel core and a semi-closed groove at the outer boundary to accommodate a 3-phase insulated winding circuit.

The rotor is wound to match the number of poles on the stator. The three terminals of a rotor and three start terminals connecting through slip rings are connected to a shaft. The aim of the shaft is to transmit mechanical power.

JR Series Wound Rotor Slip Ring Motor Application:

Slip ring lifting, Ventilator, compressor, water pump, crusher, ball mill, stock-removing machine, transport machine and other machinery.

It can be prime mover of industries like coal mine, mechanical industry, power station and different kinds of manufacturing and mining industries.

The Meaning of The JR Series Wound Rotor Slip Ring Motor Models:

JR 115 -6
J— — AC asynchronous motor
R— — Wound Rotor
11—Center height of frame
5—Core Length
6—Pole number

Note: JR series motor has two types: brushes lifting with short-circuiting device and brushless lifting with short-circuiting device.

JR Series Wound Rotor Slip Ring Motor Operation Condition:

Motor power range: 115KW-1050KW
Voltage: 380V, 415V, 480V, 660V, 690V, 3Kv, 4160V, 6Kv, 6.6Kv, 10Kv, 11Kv.
Rated frequency: 50Hz, 60Hz
Number of poles: 6/8/10/12
Cooling method: IC01
Duty: S1(continuous)
Protection: IP23, ODP (open drop-proof)
Insulation class: F
Mounting: IMB3 (IM1001), and we can design it into a vertical mount as required by customers.
Thermal protection: With 8pcs of PT100 in both bearings and windings
Ambient temperature: -15°C≤θ≤40°C
Altitude: not exceed 1000m
With anti-condensation space heater

JR Series Wound Rotor Slip Ring Motor Feature

JR series of winding three-phase asynchronous motor for the old series of motors, electromagnetic calculating the insurance coefficient, strong overload capacity.

JR series motor using total pressure rotor resistor string starts with a startup current, starting torque, and efficiency, low noise, little vibration, ventilation performance, reliable operation and easy installation.

Working of Slip Ring Induction Motor

This motor runs on the principle of Faraday’s law of electromagnetic induction. When a stator winding is excited with an AC supply, the stator winding produces magnetic flux. Based on faraday’s law of electromagnetic induction, the rotor winding gets induced and generates a current of magnetic flux. This induced EMF develops torque that enables the rotor to rotate.

However, the phase difference between the voltage and current do not meet the requirements to generate high starting torque as torque developed is not unidirectional. The external resistance of high value is connected with the circuit to improve the phase difference of a motor. As a result, inductive reactance and phase difference between I and V is reduced. Consequently, this reduction helps the motor to generate high stating torque.

Comparison of Different Deries High Voltage Motor