The Exitronix RELAY-120/277 Emergency Lighting Control Device allows local switch control of designated emergency luminaires when emergency power is provided by a generator or inverter. The RELAY-120/277 senses the loss of normal AC power and bypasses the local switch device allowing emergency power directly to the fixture regardless of switch position. The RELAY-120/277 is rated for any lamp load up to 3.8A @ 120VAC or 1.7A @ 277VAC of continuous power including LED loads per NEMA 410 standards. The RELAY-120/277 is an ideal solution for achieving increased energy savings in accordance with most energy efficiency standards. This is achieved by eliminating the need to operate the designated emergency fixtures 24/7 when emergency power is sourced from a generator or inverter.