Design and Functions
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10.3.6
Inspection / Inspection limit switches
If lift is switched to inspection, OC and NOC open. If the actual position is between upper and lower limit switch,
OC and NOC will close if a direction button is pushed, no matter if UP-, DOWN- or both buttons are pushed.
If upper inspection limit switch is over travelled, OC/NOC will only close if DOWN button is pushed.
If lower inspection limit switch is over travelled, OC/NOC will only close if UP button is pushed.
LIMAX Safe SG/SC supervises also the consistency of direction Button and real moving direction:
If the UP button is pushed and car travels upwards, OC and NOC will open.
If the DOWN button is pushed and car travels downwards, OC and NOC will open.
If both buttons are pushed at the same time, car must come to standstill respectively stay in standstill,
otherwise OC and NOC will open.
If OC and NOC are opened due to a contradiction of direction button state and real movement, they will close
again after 10s standstill and both buttons released. The connections of Safe Box with the inspection panel
should be checked in this case.
10.3.7
Behavior of NOC (informative)
If no door bridging is active, the NOC-contact always follows the status of the door circuit input.
However, the status of the door circuit input is only equivalent to the status of the door contacts (all closed
at
least one opened), if the OC is closed and there is no other interruption in the safety circuit before the door
circuit.
If the OC is opened (e.g. because the final limit switch was overrun or because the temporary reference posi-
tions have not yet been learned in teach mode), the safety circuit is interrupted and therefore no safety circuit
voltage is applied to the door input; as a result, NOC also opens.
If a recall is initiated while the OC is opened, safety circuit voltage is applied to the door circuit input because
the opened OC is bridged via recall panel.
If recall is selected when the OC is closed without a recall travel being initiated by pressing a direction button,
the safety circuit is also interrupted and the NOC opens. If a direction button of the recall panel is then pressed,
the safety circuit closes again and therefore the NOC also closes.
(This chapter serves only as information for the programmer of the control and for helping the technicians in
finding errors).
