exploring relay application

Let’s begin with the fundamentals. In the initial phases of backup generator installations, load shedding wasn’t a concern because the national electric code didn’t mandate load shedding for generators. The introduction of load shedding codes became a significant issue in various regions after their adoption.

Initially, those embracing load shedding employed readily available general-purpose contactors capable of controlling loads up to 50 amps. While these devices effectively removed the load, contactors posed challenges as they remained energized whenever the load was active in utility mode (approximately 97% of the time). This led to the generation of excessive heat and noise, along with frequent failures. In case of failure, contactors typically malfunctioned in the open position, leaving the circuit disconnected until replacement.

Recognizing the drawbacks associated with contactors, some manufacturers turned to normally closed relays as an alternative. While this addressed the issues of high failure rates and noise, these relays proved to be more expensive. Furthermore, they did not entirely resolve the challenge posed by loads exceeding 50 amps.