How to check the coil of refrigeration equipment?

- Aug 05, 2019-

1. Choose the appropriate shaking meter: if the rated working voltage of the motor under test is 380 volts, then we can choose the 500V shaking meter.

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2, shake the table flat, do a short circuit test, two watch pen short connection, shaking the handle pointer close to 0 is good.

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3, and separate the two pens, shake the handle, pointer close to infinity is good.

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4. It is better to remove the connection sheet of the three-phase motor when measuring, and the shell is grounded. Let's make up the bottom terminals of the three windings, from left to right, U, V and W.

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5\Step 1: measure the insulation resistance between the three-phase output end and the housing; E contact the motor housing; L contact the wiring terminals U, V and W respectively; shake the handle rapidly (120 turns per minute); when the pointer is stable near infinity, the insulation is good.

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6. Step 2: measure the insulation between the three contacts, U, V and W. Measure them once in pairs.

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7. It can be measured without removing the connecting piece, which is the difference between star and Angle connection. When it comes to star, the resistance between U, V and W points and the neutral point can be measured. It is more accurate to measure the resistance with a multimeter and the resistance to the ground.

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Overview of other detection motors:

1. Shake the meter. 500V is enough. Shake the insulation resistance value of the wires on the three terminal posts to the motor housing.

2, multimeter test: test U, V, W three phase resistance value, whether equal, should be about the same, too much difference can also turn, but not long, remember the larger the motor, the smaller the resistance value! But the three-phase is not 0 euro, unless you are particularly large, such as 50KW above the motor! Remember if it's a speed motor, the 6 terminals have different resistance values.

3, check the bearing, fan, general winding motor let all change! Because sometimes the bearings will burn the motor.

4. The no-load current of the motor is generally 10% ~ 50% of the rated current.

5. When the rated current of the motor is running at full load, the output power is basically 100%. Running current is small, indicating that the output power of the motor decreases, and it is running under light load.