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In the field of electric bicycles, brushless motors have become the core component of modern electric bicycle power systems due to their high efficiency, low noise, and long lifespan. As a leading manufacturer in the R&D, production, sales, and service of electric bicycle motors, Shengyi has been dedicated to the innovation and optimization of brushless motor technology since its establishment in 2003, providing high-quality and high-performance motorcycle brushless motor to global users. Today, from Shengyi's professional perspective, we will explore how to detect whether an motorcycle brushless motor is in good working condition, ensuring your riding experience is safe and worry-free.
Before delving into detection methods, let's briefly understand the basic structure and working principle of motorcycle brushless motors. A motorcycle brushless motor mainly consists of a stator, rotor, sensors, and an electronic commutator. The electronic commutator controls the current direction in the stator coil, achieving continuous rotation of the rotor, thereby driving the electric bicycle forward. Compared to traditional brushed motors, brushless motors have higher energy conversion efficiency and longer service life.
Disconnect the Power and Wire Harness
First, ensure the electric bicycle is powered off and completely disconnect all the motor plugs from the wire harness to ensure safety during the detection process.
Resistance Value Detection
Using the diode or resistance mode on a multimeter (depending on the multimeter model), connect the red probe (positive) to the thin red wire (usually the power line) in the motor's six-pin plug, and the black probe (negative) to the thin yellow, blue, green, and black wires (usually phase lines and ground line). Normally, the resistance value between the red and black probes should display above 900, indicating good insulation between the coils. If it displays 0 or infinite, there may be a short circuit or open circuit in the coils.
Next, connect the red probe to the black wire and the black probe to the thin yellow, blue, green, and red wires, observing whether the resistance value is in the range of 500-600. This step is used to check the resistance between the phase lines and the ground line to determine if there is any leakage in the motor.
Interpreting the Detection Results
Based on the detection results of the above steps, the initial judgment can be made on whether the motorcycle brushless motor has any coil short circuit, open circuit, or leakage faults. It should be noted that the resistance value range may vary for different motor models, so it is recommended to refer to the motor's manual or consult a professional when conducting the detection.
Prepare Tools and Connect Wires
Reconnect the motorcycle brushless motor to the power source and ensure all wires are connected correctly. Use the 200-volt DC voltage range on the multimeter to prepare for dynamic detection.
Rotate the Motor and Observe Voltage Changes
Fix the black probe of the multimeter on the thin black wire (ground line) in the six-pin plug, and the red probe on the thin yellow, blue, and green wires (phase lines). Then, manually or using external force, gently rotate the motor rotor while observing the voltage readings on the multimeter.
Analyzing Voltage Changes
During the rotation of the motor, the voltage displayed on the multimeter should vary between 0-6.25 volts. This is because, with the rotation of the motor, each phase coil sequentially becomes a current path, causing voltage changes. If the maximum and minimum voltage values of the three phase lines do not differ much and the fluctuation range is within normal limits, the motor is operating normally. If there are abnormal voltage fluctuations or any phase voltage is significantly lower than the others, it may indicate internal faults like coil damage or demagnetization of the magnetic steel.
As a leader in the field of motorcycle brushless motors, Shengyi always prioritizes product quality. Our electric motorcycle brushless motors have not only passed international certifications such as CE, ISO9000, ROHS, and 3C but have also undergone rigorous factory inspections to ensure each motor achieves optimal performance.
Furthermore, Shengyi provides comprehensive pre-sales consultation, mid-sale guidance, and after-sales service. Whether you are an electric vehicle manufacturer, distributor, or end-user, as long as you have any questions or needs regarding motorcycle brushless motors, we will wholeheartedly provide professional solutions and technical support.
sales@syimotor.com
+86-512-65975022
+86-512-65963935
No.588, Liupu Road, Wuzhong District, Suzhou/215124, JiangSu Province, China
