Oki OKIFAX 5400 Maintenance Manual page 313

PWU
5-7 Photosensors
The photosensors mounted on this circuit board/sensor board supervise the paper running
state during printing. These six photosensors are used in this printer as listed below. All of
their outputs enter CPU for referring to and processing by the CPU.
1)
2)
3)
4)
5)
6)
40838301TH Rev.1
PS1 (photosensor 1): PSOUT
Supervises the paper feed according to the time of arrival at the sensor and the time
of passage of paper.
PS2 (photosensor 2): WRSNS
Detects the leading part of sensor.
Supervises the paper running state.
PS3 (photosensor 3): PSIN1
Detects the leading part of the paper and gives the supervision timing for switching
from hopping operation to feeding operation. Supervises the paper running state and
the paper size according to the paper arrival time and running time.
PS4 (photosensor 4): PAPER
Detects the end of the paper.
PS5 (photosensor 5): PSIN2
Not used
PS6 (photosensor 6): TONER
Detects the lack of the toner.
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