An audible and/or visual alarm device in the elevator pit that can be activated manually or automatically when a person is trapped or in distress in the pit, connected to a remote monitoring centre or building management system.
Full Definition
EN 81-20 §5.2.3 and EN 81-28 (remote alarm) require that provision be made for a person inadvertently trapped in the elevator pit to communicate with and summon assistance. The pit alarm system comprises: (1) manual alarm button — yellow push button mounted adjacent to the pit stop switch at ≤ 2 m from the pit access ladder, activating a buzzer or siren ≥ 65 dB(A) audible from the machine room or building manager's station; (2) automatic flooding/entrapment detector — optional but increasingly specified, using a float switch (water level alarm) or PIR sensor (person detection with time delay); (3) remote transmission — EN 81-28 mandates a two-way voice communication system connecting the pit, car, and a continuously attended response centre within 60 s; the pit alarm is integrated into the same GSM/PSTN/VoIP remote alarm transmitter as the car intercom; (4) indicator lamp — a red indicator at the lowest landing indicates pit alarm activation to first responders. Battery back-up for the alarm circuit is required by EN 81-28 §6.2 (minimum 1 h at 20 °C). Pit alarm wiring must be run in a separate conduit from power circuits.
