Testing the motor performance of water well machinery requires measuring key indicators such as winding resistance, insulation resistance, and operating status to ensure the motor has no short circuits, open circuits, or insulation failures.
Preparation
Power Off and Discharge: Ensure the motor is completely powered off and discharge the windings to prevent residual charge from affecting the measurement or causing danger.
Tool Preparation: Use a digital multimeter (higher accuracy). Check that the probes are intact and ensure reliable contact.
Environmental Inspection: Keep the motor surface dry and clean, avoiding moisture or oil contamination that could interfere with the test results.
Winding Resistance Testing
Range Selection: Set the multimeter to the resistance range (200Ω or 2kΩ).
Measurement Method:
Single-phase Motor: Measure the resistance of the running winding (U1-U2) and the starting winding (Z1-Z2). Normal values are a few ohms to tens of ohms. If the display shows "OL" (infinity), it indicates an open circuit in the winding; if it is close to zero, it may indicate a short circuit.
Three-phase motor: Measure the resistance between the U-V, V-W, and W-U phases respectively. The resistance values of the three phases should be basically consistent (deviation ≤10%). If any phase is abnormal, it indicates that the winding of that phase is damaged.
Precautions: Do not touch the metal parts of the test leads during measurement to prevent interference from human body resistance; temperature will affect the resistance value, it is recommended to test at room temperature.
