1 - access light barrier

В тексте: After the operator has made sure that there are no personnel or objects in the open aisle, the enabling button must be actuated there. The green "Ready" lamps on the carriages light up after passing through the access light barrier within the "dead time". The desired aisle can now be moved into by means of the "open" button on the carriages. If the access light barrier is interrupted during the movement, the installation stops. It must be enabled once more.

2 - safety light barrier

В тексте: The foot-level safety light barriers for track safety are active in the direction of motion during the movement. Any interruption of the foot-level light barriers or actuation of the emergency stop buttons on the carriages or the switch cabinet (safety circuit) result in
the standstill of the installation and the indication of a fault.

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