Containing both a 24VDC supply and a 20A line voltage relay for most models, the Leviton compact power pack provides low voltage power and line voltage control for Leviton Occupancy Sensors. Versions include Auto-ON and Manual-ON inputs for occupancy sensors, Hold-ON and Hold-OFF capabilities, and a local input for momentary or maintained dry contaCT'switches. The OSP Power Pack Series is also used to supply power to the OSA Add-A-Relay model. The Power Pack conveniently mounts in a knockout hole of a standard junction box. The unit can be placed inside or outside the junction box with a simple twist-on nut. The internal relay can control up to 20 Amps at either 120, 230, or 277 VAC ballast load, 15 Amp for 347 VAC ballast load. 15 Amp FL, 347VAC 60Hz, power pack for occupancy sensor with HVAC relay 0.5A 125 VAC 1.0A 30VDC. Self-contained transformer amp; relay Regulated 24 VDC current - 150 mA output Mounts inside or outside junction box - or inside fluorescent ballast cavity Fast Installation Companion Add-A-Relay provides additional capacity (OSA20-R00)