Ricoh FT5540 Service Manual page 323

During two-sided original mode, three sensors detect misfeeds. The ON checks for the
original entrance sensor and the registration sensor are the same as when in single-sided
mode.
The DF CPU checks if the original entrance sensor has been deactivated 1,250 milliseconds
after the registration sensor is activated (original sensor OFF check).
The DF CPU checks if the registration sensor has been deactivated 175 milliseconds after the
original entrance sensor is deactivated.
When the original is inverted for the first time, the ON check for the exit sensor is 1,250
milliseconds after the inverter gate solenoid turns on. The OFF check for the exit sensor is
1,250 milliseconds after the belt drive motor reverses.
When the original is fed out, the OFF check and ON check for the exit sensor are the same as
in the single-sided mode.
When a misfeed is detected, the DF CPU stops the DF and sends a misfeed signal to the
copier. The misfeed condition is cancelled by deactuating the lift switch.
8-15
31 August 1989