ELEVATOR SYSTEM WITH A SAFETY CHAIN

An elevator system (2) is provided which comprises a plurality of hoistway doors (10a, 10b, 10c), a corresponding plurality of sets of non-contact switches (12a, 12b, 12c), each set arranged to detect when a respective hoistway door (10a, 10b, 10c) is open, and a monitoring device (26). Each set of non-contact switches (12a, 12b, 12c) comprises a first non-contact switch (14a, 14b, 14c) arranged to open when the respective hoistway door (10a, 10b, 10c) is open and a second non-contact switch (16a, 16b, 16c) arranged to open when the respective hoistway door (10a, 10b, 10c) is open. The first non-contact switches (14a, 14b, 14c) of the plurality of sets are connected in series to form a first electrical path (22) and the second non-contact switches (16a, 16b, 16c) of the plurality of sets are connected in series to form a second electrical path (24). The monitoring device (26) is arranged to measure an electrical property of the first electrical path (22) and an electrical property of the second electrical path (24) to detect when a hoistway door (10, 10b, 10c) is open.