A ground fault relay is a protective device used in electrical systems to detect ground faults, which occur when electricity unintentionally flows to the ground. This can happen due to insulation failure or equipment damage, posing a risk of electric shock or fire. The relay monitors the current flowing through the system and can quickly disconnect the power supply if it detects an imbalance, ensuring safety. These relays are commonly used in various applications, including industrial machinery and residential electrical systems. They are essential for protecting both people and equipment from the dangers associated with ground faults, contributing to overall electrical safety and reliability.