Starting and working capacitors are used to start and operate electric motors operating in a single-phase network of 220 V.Therefore, they are also called phase shifting.The installation location is between the power supply line and the motor starting winding.
Symbol of capacitors on the circuits
The main parameters of capacitors
Capacitor capacitance – characterizes the energy that the capacitor is able to accumulate, as well as the current that it can flow through itself. It is measured in Farads with a multiplying prefix (nano, micro, etc.).
The most used ratings for working and starting capacitors are from 1 μF (μF) to 100 μF (μF).
The nominal voltage of the capacitor is the voltage at which the capacitor is able to operate reliably and for a long time, keeping its parameters.
Checking the starting and working capacitors
You can check a capacitor using a capacitor capacitance meter; such devices are available both separately and as part of a multimeter a universal instrument that can measure many parameters.
- Consider checking a multimeter.
- de-energize the air conditioner
- discharge the capacitor by shorting its outputs
- remove one of the terminals (any)
- set the device to measure the capacitance of capacitors
- Lean probes against capacitor leads
- read capacity value from the screen
After connecting the probes to the capacitor terminals, we wait for indications on the screen, for example, the measurement time of a 40 μF capacitance with the first device is less than one second, with the second more than one minute, so you should wait.
If the nominal value does not correspond to that indicated on the capacitor case, then it must be replaced and if it is necessary to choose an analogue.
Replacement and selection of start / run capacitor
If there is an original capacitor, then it is clear that it is simply necessary to put it in its place of the old one and that’s all. Polarity does not matter, that is, the capacitor leads do not have plus + or minus signs and can be connected as you like.
Electrolytic capacitors cannot be used categorically (they can be recognized by their smaller size, with the same capacity, and the designation plus and minus on the case). As a consequence of the application thermal destruction. For these purposes, manufacturers specifically produce non-polar capacitors for use in the AC circuit, which have a convenient mount and flat terminals for quick installation.
Condenser replacement technique
Disconnect in turn the wires from the old capacitoron the block experts can connect the wires from the fan condenser to the compressor condenser (any output, non-polar capacitors), from the compressor’s working winding (С -common), from the fan’s working winding, from the power supply connector (L or N, depending on the circuit).
Air conditioner capacitor replacement experts connect the wires from the compressor and the fan to the appropriate capacitors.It is possible not to remove the old capacitor, since there is enough space in the case, but to use its common output as a connector by connecting the output from two capacitors to it.