PRO TECHNICIAN

Refrigeration System

Magnetic Clutch

Click on the appropriate button in the illustration.
1. Function
The magnetic clutch is driven by the engine through the drive belt. The magnetic clutch is a device to connect the engine and the compressor together. The magnetic clutch drives and stops the compressor as necessary, based on the cooling demands
2. Construction
The magnetic clutch consists of a stator (electromagnet), pulley, center piece, and other components. The center piece is installed together with the compressor shaft and the stator is held on the front housing of the compressor.
3. Operation
When the magnetic clutch relay is switched on, current passes through the stator coil forming a strong electromagnet with the stator. As a result, the stator attracts the centre piece through the magnetic force and connects the compressor drive shaft together with the pulley. When the magnetic clutch relay switches off, current no longer passes through the stator, which causes the centre piece to return to it’s original position while the pulley continues to idle.
When the magnetic clutch is off, current doesn't pass through the stator, which causes the center piece not to be pulled and only the pulley turns idle.

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