Specifications

C-5
PagePro25
2-1-2. Sensors for Tray 1
(1) 1st Cassette Set Sensor (PC6)
This sensor detects the installation of the 1st paper cassette in the tray 1. This sensor uses a photointerrupter.
If the 1st paper cassette is not installed in the tray 1, the projection of the paper cassette comes off the sensor which is
mounted on the printer. In this case, the light emitted from the LED of the photointerrupter reaches the phototransistor of
the photointerrupter and the phototransistor turns ON. Accordingly, the output of the phototransistor, i.e., the output of the
sensor is “L”.
When the 1st paper cassette is installed in the tray 1, the projection of the paper cassette engages with the sensor. In this
case, the light emitted from the LED is blocked by the projecting and it does not reach the phototransistor. As a result, the
phototransistor turns OFF and its output is “H”.
The CPU on the main board can know whether the 1st paper cassette is installed in the tray 1 or not by sensing the out-
put from the sensor (PC6).
(2) 1st Cassette Paper Empty Sensor (PC4)
This sensor detects the paper empty status of the 1st paper cassette. The sensor uses a photointerrupter. When paper
runs out in the 1st paper cassette, paper empty occurs.
When paper is present in the paper cassette, the lower part of the sensor arm is pressed by the paper and the projection
of the upper part of the sensor arm comes off the photointerrupter. Thus, the light from the LED of the photointerrupter
passes in the photointerrupter and the photointerrupter turns ON. As a result, the output of the photointerrupter is “L”.
When paper runs out in the paper cassette, the lower part of the sensor arm lowers with its weight so that the projection
of the sensor arm engages with the photointerrupter. Thus, the light from the LED is blocked by the projection and the
photointerrupter turns OFF. As a result, the output of the photointerrupter is “H”.
1st Cassette Set Sensor (PC6)
1st Paper Cassette
Light is blocked:
Output = H
Light passes:
Output = L
PC6 is mounted on the Printer.
[Cassette is not installed.]
[Cassette is not installed.]
Photointerrupter Circuit
When light passes: OUT = L
When light is blocked: OUT = H
Photo
Transistor
Photointerrupter
[Main Board]
LED
OUT
1st Cassette Paper Empty Sensor (PC4)
Light passes:
Output = L
Paper
Light is blocked:
Output = H
[Paper is present.]
[Paper empty]