How a Control System Works within an Automatic Transfer Switch

Ordinarily, normal power is provided by a utility company and connected to onsite applications. When the primary power source has ceased to work, power from a new or used generator can be either manually or automatically transferred to the onsite application via a transfer switch. A transfer switches’ primary job is to redistribute power from a grid to a backup source of power. This article will explain how the control panel directs an automatic transfer switch.
The control panel system of a transfer switch is what makes the unit automatic in nature. Manual transfer switches are operated by onsite personnel and are used in situations where the load is not of an emergency nature requiring immediate restoration of the power supply. With an automatic transfer switch, power failures are detected immediately and the transition from utility power to generator power is seamless. The control panel’s job is to detect a power failure and initiate procedures to start the new or used generator’s engine. Once the new or used generator reaches the correct voltage and frequency (for the end use application) the control system signals the switch to transfer from the normal source of power to the generator. The engineering behind an automatic transfer switch is quite complex as time delays and other components play a pivotal role in obtaining instantaneous backup power.