ELEVATOR SYSTEMS

An elevator system (201) includes an elevator car (203), a controller (215), a position reference system (234; 213) configured to provide a position of the elevator car (203) and at least one safety device (230) configured to indicate a potential hazard within the elevator system (201). When the actual position of the elevator car (203) cannot be determined using the position reference system (234), the controller (215) is configured to calculate at least one potential position of the elevator car (203) based on an assumed motion profile (237). The controller is configured to allow the elevator car (203) to move whilst no safety device (230), which corresponds to the at least one potential position of elevator car (203) is triggered and to stop movement of the elevator car (203) when a safety device (230) which corresponds to the at least one potential position of the elevator car is triggered.