Replace the motor if it is burned, the shaft is jammed, or if there is any sign of damage. To troubleshoot a split-phase motor, apply the following procedure: Turn power to motor OFF. How can I troubleshoot a split phase motor? If the meter reads infinity, an open circuit is present. If the meter reads zero, a short is present. Since the windings are in parallel, their combined resistance is less than the resistance of either winding alone. The ohmmeter will read the resistance of the starting and running windings. How does the ohmmeter work on a single phase motor? However, if the motor is more than 10 years old and less than 1 HP, the motor is usually replaced. If the problem is in the centrifugal switch, thermal switch, or capacitor, the motor is usually serviced and repaired. Most problems with single-phase motors involve the centrifugal switch, thermal switch, or capacitor (s). When do you need to replace a single phase motor? Check the motor winding resistance or ohms reading with a multimeter. Check that the correct voltage is applied to the motor.
How to test and check single phase electric motors?įor single phase motors, the expected voltage is about 230V or 208V depending whether you are using the UK or America voltage system. The meter should start at zero and then moving slowly toward infinity.
Touch the meter leads to the corresponding leads on the capacitor, red to positive and black to negative. To test the capacitor with a multimeter, set the meter to read in the high ohms range, somewhere above 10k and 1m ohms. How do you check capacitor polarity with a multimeter? Capacitor motors also have different types based on the role of a capacitor. While capacitor motors run with the help of capacitors. Shaded pole and split phase single-phase motors do not require a capacitor to run. Can a single-phase motor run without a capacitor? Typically, there is one power wire-the phase wire-and one neutral wire, with current flowing between the power wire (through the load) and the neutral wire. Single-phase power is a two-wire alternating current (ac) power circuit. How many wires does a single-phase motor have? You should test the windings for a “short to ground” in the circuit and open or shorts in the windings. To begin, set the multimeter to read ohms and then test the motor’s wires and terminal. Inspect the Motor Windings With a Multimeter First and foremost, you’re going to need a multimeter to test the windings. How do you check motor windings with a multimeter? However, before springing for a replacement, you may want to conduct some simple tests to see if the motor can still be repaired. Things You’ll Need While a single-phase motor is normally resilient and can operate unhindered for decades, there will come a time when it will break down and cause problems. Should a single-phase motor have continuity? If the motor does not start, use a voltmeter, such as a Fluke 87V Industrial Multimeter, to check for voltage at the motor terminals.Check to determine if the motor is controlled by a thermal switch.Troubleshooting split-phase (single phase) motors How do you troubleshoot a single-phase motor? For single phase motors, the expected voltage is about 230V or 208V depending whether you are using the UK or America voltage system. Any value greater 0.5 ohms indicate trouble with the motor.
A good motor should read less than 0.5 ohms. With a multimeter, measure the resistance between motor frame (body) and earth. How do you test a single-phase motor with a multimeter?