The NSi Industries 5237-UL is a NEMA twist-lock type photocontrol designed for the automatic control of outdoor lighting applications, including street, highway, roadway, area, parking, flood, and security fixtures. This electronic photocontrol operates on a wide voltage range of 105 to 305 VAC at 50/60 Hz and is rated for loads up to 1000W Tungsten, 1800VA Ballast, and is compatible with LED fixtures. It features a UV-stabilized polycarbonate housing and an integral lens, protecting against moisture and weather elements. Light activation occurs at 1.5 foot-candles (FC) and deactivation at approximately 2.25 FC. The unit incorporates a molded, sealed, IR-filtered silicon sensor designed to mimic human eye response, a 360 Joule MOV surge protector, and a DC relay with a fail-ON mode and a 2-5 second OFF delay to prevent false switching. It measures approximately 3.187 inches in width and 2.187 inches in height. The photocontrol is UL 773, CSA, and ANSI C136.10 compliant and comes with an 8-year warranty.