What does a potential relay do?

A potential relay is an electrical device that plays a crucial role in the operation of refrigeration and air conditioning systems. Its primary function is to manage the start and stop of the compressor motor. It operates based on the potential (voltage) measured across the relay contacts.

When the voltage is high, which often indicates that the system is at normal operating conditions, the potential relay opens the switch. This is important because it prevents the compressor from continuously running under conditions that may be detrimental to its operation, such as during low refrigerant conditions or other fault scenarios. As the voltage decreases to a certain threshold, which may indicate the end of the starting sequence or an irregular system condition, the relay recognizes this state and closes the switch, allowing current to flow and enabling the compressor to run as needed.

This functionality helps ensure both efficient operation and protection of the system by controlling the compressor based on voltage levels, differentiating it from simple high or low voltage operations and ensuring that the system does not operate under potentially harmful conditions.