Refrigerator Compressor Testing
With the compressor being the most expensive component in the system, it is wise to be sure that it was bad before condemning it. For this reason, you should learn a systematic method of diagnostics compressor. You will need a good ohmmeter that can be measured with one ohms up to 20 kOhm. Meter for example, it can be purchased in the price range from $20 to $125, depending on the quality. The landlord can do and less expensive, due to the fact that it will not be much use of techniques will give it.
This procedure is used also in case, if the compressor is not running when called to do so. Always remember, safety first. Before opening condensing unit turn off the electric power to the device. With the service panel removed, look with your eyes, before you touch anything. There must be some type of flash lid to cover the terminals of the compressor. This is the main safety device for protection techniques from electric shock when the device is in the works and it protects the equipment from pressure from oil, if one of the terminal goes down and blow out her grief.
It is not assumed that the oil in the unit clean. In most units refrigeration oils the net; however, in some cases, oil pollution. Education sulphurous acid could take place inside the failed unit. This acid can be dangerous to the eyes and skin. For this reason, do not assume anything; be sure and caution. Removing the cover, you will notice that the terminals are located in the approximate order, as shown in Fig. 3-11. Below is a list of electrical failures that you're testing.
Grounded compressor (short circuit). This condition occurs when the winding insulation of the electric motor drive leakage of electricity began compressor body. Blown fuses result.
To open a factory. A condition that occurs when a conductor of one of the parts of the motor windings.
Locked rotor. This condition occurs when either the crankshaft bearings capture due to lack of lubrication, or compression breaks within the compressor shell squeezing the crankshaft. In the case of single-phase units, the same locked rotor condition will be a witness, if the system has a start-up component.
Multimeter allows to diagnose internal fault in the electrical equipment of the compressor. Rang from the compressor; it means accepting continuity. Make sure that the power is off. If necessary, turn on the meter volt AC and check it out. Sometimes the gap leaves blade does that broke away from the main control panel. After checking voltage, mark the wires connected to the terminals so that they can be returned to the same position when re-assembled. There are many ways to mark them as different colors tape, black bars electricians tape notch with the knife blade. What ever works for you is suitable. The wires must be removed from the compressor, to prevent tension from other circuits. For example, 240 volt compressor can have a 120 volt condensation of the fan motor. It is possible that you could think of neutral leg 120 volt circuit, as grounded compressor.
Zero your counter. Make sure that it rests on the infinity. This is done with the help of a small screws at the base of the arrow indicator. Then touch the two probes together and turn selector switch in position X1000 scale. The needle should distract zero ohms. If you do not make adjustments with a little handle your counter to zero...