Product Overview

1. The high-efficiency high-voltage YX-series three-phase induction motors are newly developed products optimized from the original Y, YKS, and YKK series motors, in alignment with China’s national policies promoting high-efficiency energy-saving motors. Their energy efficiency labeling complies with the IEC 60034-30 standard for rotating electrical machines issued by the International Electrotechnical Commission (IEC). These motors are branded as YX, YXKS, and YXKK high-efficiency high-voltage three-phase induction motors.

2. The power ratings, mounting dimensions, and tolerances of this motor series conform to the Chinese national standard GB 755 “Rotating Electrical Machines—Ratings and Performance”, the IEC 34-1 standard “Rotating Electrical Machines—Ratings and Performance”, GB/T 13957, and mechanical industry standards JB/T 7593, JB/T 10315.1, and JB/T 10315.2. Their efficiency meets the IE2 high-efficiency motor standard and qualifies them as products under China’s Energy-Saving People’s Benefit Program, significantly reducing users’ operating costs.

3. The motor enclosure protection rating is IP23/IPW24/IP44 or IP54, complying with GB/T 4942.1 and IEC 34-5 “Degrees of Protection Provided by the Integral Design of Rotating Electrical Machines (IP Code)”.

4. Motor cooling methods comply with GB/T 1993 and IEC 34-6 “Methods of Cooling Rotating Electrical Machines”, and include IC01, IC81W, IC611, and IC616. Other cooling methods can be supplied upon user request.

5. The motor structure and mounting configuration is IMB3 (horizontal with feet), conforming to GB/T 997 and IEC 34-7 “Types of Construction and Mounting Arrangements for Rotating Electrical Machines”.

Product Features and Structural Description

Common Failures of High-Efficiency High-Voltage Motors and Root-Cause Analysis

Failure Phenomenon:Motor temperature is excessively high, yet current remains within rated limits.

Cause:1. Ambient temperature is too high. 2. Motor ventilation ducts are blocked. 3. Excessive oil sludge and dust on the motor impair heat dissipation.

Failure Phenomenon:Motor fails to start and produces no sound.

Cause:1. Fuse has blown. 2. Starter has tripped. 3. No power supply.

Failure Phenomenon:Motor emits explosive sounds during operation.

Cause:1. Temporary coil-to-ground fault. 2. Temporary coil short-circuit.

Failure Phenomenon:Motor speed is low after startup.

Cause:1. Supply voltage is too low. 2. Motor is overloaded. 3. Stator winding is shorted. 4. Rotor shorting ring, cage bars are fractured or have cracked welds. 5. Motor wired for delta connection is incorrectly connected in star configuration.

Failure Phenomenon:Motor fails to start and emits a humming sound.

Cause:1. Bearing failure. 2. Abnormal air gap between stator and rotor causing contact. 3. Driven machinery is jammed. 4. One phase of the power supply line is open, one fuse has blown, or one phase winding of the motor is open-circuited.

Failure Phenomenon:Fuse blows during motor startup.

Cause:1. One stator winding phase is reversed. 2. Bearing failure. 3. Operator error during startup. 4. Stator winding short-circuit or ground fault. 5. Drive belt is overly tight. 6. Driven machinery is jammed.