In modern electrical systems, one of the most critical aspects of maintaining safety and longevity is protecting electrical equipment from potential damage due to excessive current flow. Overload Protection Relays are an essential component that safeguards various electrical devices, such as motors, transformers, and circuits, from overloading, which could otherwise lead to malfunction or failure. These relays are designed to monitor the current passing through a circuit and disconnect the power supply if the current exceeds a predetermined safe limit, ensuring the safety and durability of the system.

What is an Overload Protection Relay? An Overload Protection Relay (OPR) is an electrical protective device designed to prevent electrical circuits or machinery from operating under overload conditions. These relays are integral in preventing overheating, which can cause insulation failure, fire, or even permanent damage to electrical equipment. The core function of an overload relay is to monitor the current flowing through a circuit and respond by disconnecting the circuit if the current surpasses the preset threshold, which may indicate an overload or fault condition. The relay works by detecting the heat generated by excessive current. Overload protection relays use different mechanisms to achieve this, with thermal and electronic being the most common types.