AB 121609, part of the FIbox product line, is an automatic transfer switch (ATS) for critical power applications. It is enclosed in an IP54-rated fiberglass reinforced polyester enclosure, enabling it to provide complete, secure protection from the elements. The switch is capable of switching from utility power to generator power, and back again, with a rated transfer time of less than 4 seconds. The switch can be operated either manually, or automatically; when it is operated automatically, it can also be equipped with various control options, such as thermistor, manual contactor, and digital IO control. Additionally, the switch includes an optional built-in time clock and relay for scheduled control. Its control board is equipped with an LCD display to show the status of the transfer. The switch also features an emergency stop function and an emergency manual override feature.