TUBE 1394558 - Caterpillar

Illustration 1 g00891196
(1) Low pressure switch (2) High pressure switchThe high pressure switch and the low pressure switch detects pressure in the cooling circuit. When the pressure is abnormal, the switch stops the compressor in order to prevent damage to the components of the cooling circuit. The switch detects abnormally high pressure. The switch detects abnormally low pressure.If the pressure between the compressor and the expansion valve decreases abnormally, the switch cuts the supply of power to the magnetic clutch of the compressor. In low pressure conditions, the compressor may not have enough compressor oil or refrigerant. Cutting the power helps to prevent a seizure of the compressor.If the pressure between the compressor and the expansion valve increases abnormally, the switch cuts the power supply to the magnetic clutch of the compressor.