A door system in which opening or closing requires a manual push but is assisted by a spring or motor.
Full Definition
An elevator semi-automatic door is a landing or car door system in which one phase of the operation — typically opening — is initiated by the user or the elevator car engagement mechanism, while the closing phase is performed automatically by a spring, counterweight, or low-power motor after a set dwell time. Semi-automatic doors were prevalent in older residential and low-traffic commercial elevators installed before the widespread adoption of fully automatic centre-opening power doors under EN 81-1:1998 and later EN 81-20. They are characterised by swing-type or collapsible grille car gates combined with hinged or sliding landing doors. Under current EN 81-20, semi-automatic doors fitted with spring-return or counterweight-closing mechanisms must be equipped with a door contact verified in the safety circuit; the closing force must not exceed 150 N to prevent entrapment injury, and the door must re-open upon contact with a person. EN 81-80 flags the absence of a power door operator as a significant safety deficiency in passenger lifts carrying more than a defined occupancy, and recommends upgrade to fully automatic power doors as part of a safety improvement programme. Residual semi-automatic door installations are maintained with focus on hinge integrity, return spring tension, and contact switch reliability.
