The EiB146e Optical Smoke Alarm is fitted with a proprietary photoelectric sensor to quickly sense low energy smoke particles from smoldering fires. Powered by 230V AC with a 9V user replaceable Alkaline battery backup to ensure continuous opera????on (up to 3 years) in the event of a power failure. The Alarm is supplied with the "Easi-fit" base to facilitate quick and simple installation, combined with easy detector head removal and replacement. The Easi-fit base automatically connects both mains power and battery as the detector head slides on. The EiB146e may operate as a standalone Alarm or may be interconnected to other Alarms via a wired or wireless system. For a wireless system each Alarm must be fitted with an EiB168RC RadioLINK base. When interconnected all Alarms in the system will sound if a fire is detected. The Alarm self-checks its sensor, battery voltage and internal circuitry every 40 seconds. A fault condition will be indicated by a short beep every 40 seconds. The Test / Silence button allows the user to check the opera????on of the Alarm. The Silence function allows the Alarm / System to be silenced in case of a false / nuisance alarm, e.g. cooking fumes. The memory feature allows an Alarm that has previously activated to be easily identified. This is indicated by 2 red led flashes every 40 seconds for 24 hours (after the event).