OKIDATA OF2200, Руководство по обслуживанию

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Photosensors
· Outlet Sensor (PS1) ON: Paper is present
Detects paper jams at the paper exit path.
· Paper Sensor (PS2) ON: Paper is present
Along with the outlet sensor, is used to monitor paper feed and paper length.
· Inlet Sensor 1 (PS3) ON: Paper is present
Detects the leading edge of the paper.
Used to determine when to switch from the hopping to the feeding operation.
· Paper End Sensor (PS4) ON: Paper is present
Detects the presence of paper in the cassette.
· Inlet Sensor 2 (PS5) ON: A4 or larger
Detects the width of the receive paper.
· Toner Low Sensor (PS6)
Detects a low toner condition
Cover Open Switch
Whenever the stacker cover is opened, the cover open switch is turned OFF. This removes the + 38 vdc
source voltage from the high-voltage generation circuit. As a result, all high-voltage outputs are disabled.
The CVOPN signal is sent to the main control board and the cover open routine is performed. The
message COVER OPEN will be displayed on the operator panel.
High-Voltage Circuits
The following voltages are generated for use in the electrostatic printing process.
OUTPUT VOLTAGE USE
SB1/SB2 - 450 vdc Toner Supply Roller
DB1/DB2 +/- 300 vdc Toner Development Roller
TR1/TR2 + 1 Kvdc/-750 vdc Transfer Roller
CH - 1.3 Kvdc Charging Roller
CB + 400 vdc Toner Cleaning Roller
1.4.05 Fuser Unit
The fuser unit is controlled by a thermistor, the printer interface gate array (PIGA), an LSI, and the CPU to
keep the heat roller surface temperature within a predetermined range (about 150 degrees Celsius). A
thermal fuse within the fuser unit prevents abnormal temperature rises in case the thermistor fails.
NOTE:
The CPU checks for an open circuit in the thermistor at power-on. A fuser alarm is set if this error is
detected.
The CPU also sets a fuser alarm if the proper temperature is not attained within a specified period of time
after power-on.