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Two sensors, one for confirming drop off and one for pick up (recommended)
for the primary position (Pick) : select the corresponding digital input with normal logic (when the sensor is HIGH it triggers a Palletize action from the Pick position)
for the secondary position (Drop) : select the same digital input but with "inverse" logic (when the sensor is LOW it triggers a Depalletize action from the pallet to the Drop position)
One sensor alternating between signals; “High” for box presence on the conveyor (palletizing) and “Low” for conveyor empty (depalletizing)
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