Ricoh D025 Service Manual page 1280

Tray Operation
The edge depressors touch the top of the stack, and they are connected to the paper
height sensor [5], so this action checks if it is necessary to move the tray up or down.
After 200 ms if the paper height sensor is ON, the tray lift motor switches ON and
raises the tray.
If the paper height sensor is OFF, the tray lift motor lowers the tray until the paper
height sensor switches ON, pauses for 100 ms, switches on again briefly to raise tray
to the prescribed position to receive the next stack.
D372 46 SM