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Compressors play a very important role in many industrial products. For the compressor to perform its functions better, it is very necessary to understand every knowledge about the compressor.
As we all know, for everyone engaged in the refrigeration compressor industry, the wiring method of air conditioning compressors is a topic that can never be avoided. I also saw on Google that many people search about the C, R, S wiring issues of the air conditioner compressor. Today, we will briefly talk about this topic. I hope that after reading this article, you will have a very clear understanding of the CRS wiring method of household air conditioning compressors.
1. What are the C, R, and S of the refrigeration air conditioning compressor?
The air conditioning compressor terminals C, R, and S represent the three-phase AC input lines. These letters are:
C – Common Terminal C, also known as the common terminal, is the basic aspect of compressor wiring. It is the point at which multiple circuits are connected and share a common voltage reference. In the compressor, terminal C is usually connected to the control circuit and the power circuit. This terminal plays a vital role in maintaining the electrical balance required for the proper operation of the compressor.
In fact, terminal C ensures that the control circuit receives the correct voltage to start and regulate the operation of the compressor. It acts as a bridge between the individual components, facilitating effective communication and coordination within the compressor system.
Briefly, “C” is usually a black or blue wire, which is connected to the neutral wire of the power supply.
R——Run terminal Terminal R is a critical aspect of the compressor’s ability to operate. When the compressor is running, the R terminal needs to power the compressor motor. When the air conditioner compressor receives the start signal, the R terminal energizes the compressor motor and makes it run at the set speed.
Whether the R-terminal wiring is correct is directly related to the integrity of the compressor system. Successful and correct wiring of the R terminal can ensure the compression effect of the compressor, Further ensure the good effect of air conditioning.
“R” terminal usually is the red wire, which is connected to the hot wire of the power supply.
Terminal S—–Means “Start”, and usually is the white or yellow wire. “S” usually needs to connect to the power of the starting capacitor or starting inductor. “S” plays a very important role in the start-up state of the air conditioner compressors, it can ensure the rotation speed of the compressor. Especially, when the application has a high request on frequently starting, it can protect the compressor.
Specifically, when the air conditioner compressor starts, power enters the compressor from the start line (S) and causes it to start running. Once the compressor reaches normal operating speed, power flows into the compressor through the operating line (R). The common line (C) connects the central point of all power lines so that power can flow normally to and from the compressor.
2. How to know which is “C(common)”? Which one is “R(Run)”? Which one is “S(Start)”?
We know that air conditioning compressors, whether they are rotary compressors, scroll compressors, or piston compressors, are divided into single-phase and three-phase. Next, we will explain it in two parts: single-phase refrigeration compressor and three-phase refrigeration compressor. Let’s first understand the C, R, and S of single-phase compressors.
2.1 Identify them according to the compressor manufacturer’s logo. Most compressors will have specific C, R, and S clearly marked on the terminals and terminal covers. This is very simple.
2.2 For compressors without specific identification, we need to distinguish them ourselves and find out C, R, and S.
(1)For a single-phase refrigeration compressor (we take a compressor with 220V voltage as an example), if you find that there is no mark on the compressor terminal, you can use a multimeter (Rx1Ω gear) measurement method: measure the resistance of the three terminals respectively. If there is no mark on the two terminals, When the maximum resistance value is measured, the unmeasured terminal is the common terminal (C), (running winding resistance + starting winding resistance = maximum measured resistance value). After determining the common terminal (C), you can use the common terminal (C) to measure the running winding resistance and starting winding resistance respectively.
(2)If the refrigeration compressor has a three-phase 380V voltage, connect the three live wires directly to the compressor terminals, then turn on the power, and observe whether it is running forward or reverse. The air conditioner compressor will make loud noise and vibration in reverse rotation, and the forward rotation will be relatively stable. It is found that it is a reverse rotation. Turn off the power immediately after the transfer, and then swap any two live wires. This is the correct wiring method.
3. What are the operating methods or steps for C, R, and S wiring?
1)Turn off the power first to ensure safety;
2) Select the correct power supply voltage and current level according to the model and power supply requirements of the air conditioning compressor;
3) Peel off a small section of the outer sheath of the power cable and use wire strippers to clean the wire ends.
4) Connect the power cord to the C, R, and S terminals respectively. If necessary, use wire cutters to cut the ends of the wire to the appropriate length.
5) Make sure all connections are tight and there are no loose or exposed wires.
6) Check whether the wiring is correct according to the electrical diagram. After confirming that it is correct, you can try to reconnect the power supply to test whether the compressor is operating normally.
Attention:
1) Implemented in case of power outage;
2) If there is no relative professionalism, please seek professionals;
3) Using the wrong level of voltage and current may cause damage to the compressor or cause a fire.
4. How to remove the air conditioning compressor terminal ?
1) Turn off the power;
2) Use appropriate tools (such as flat-nose pliers or flat-nose screwdrivers) to remove the screws or circlips on the connection line.
3) Do not damage the wiring and terminals of the compressors.
4) If you need to replace or connect the cable of the compressor, please choose the same model and parts as the original one, and reconnect according to the correct method.
After rewiring, be sure to perform an electrical test to make sure the air conditioning system is working properly.
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