Aritech PM841 is a switch-mode power supply accepting 230 VAC input and delivering 12 VDC at 1 A, with a 0.5 A battery charge circuit for a back-up battery up to 7.2 Ah. The metal cabinet houses two status LEDs indicating mains and battery condition, providing an uninterruptible supply to intrusion and access-control equipment. It is intended for stand-alone security peripherals that do not have their own PSU. Typical application is powering keypads, expanders, sirens and access readers in security installations.