7015
Tray present sensor
Detects the presence of the tray in the printer.
Bin full sensor
Detects whether the standard bin is full by moving the actuator up and down.
Toner density sensor
Detects a pre-placed toner patch and image on the photoconductor (drum) and outputs pulses when the central line
of the patch image aligns with the central line of the detector. The sensor outputs pulses at the timing the patch image
passes the sensor. Therefore, observing changes of intervals at which pulses are output leads to toner density detection.
Pass through sensor (option tray)
Detects when the media from the option tray passes. This will trigger the pick roller to pick the next media.
Front door sensor
Is a safety switch to cut off a 24 V DC power supply from the LVPS card assembly to the HVPS card assembly, printer
system card assembly and to the main drive motor assembly, while the printer front door assembly is open.
Other key components
Cooling fan
Discharges air from the printer to prevent excessive temperature increase.
Power supply
The power supply has two main sections: the HVPS and LVPS. The HVPS card assembly generates AC power and feeds
it to the developer roll, the transfer roll assembly and the charge roll assembly. The LVPS card assembly generates low
voltages: 5 V DC for logic circuits, 5 V DC for laser diodes and 24 V DC for cooling fans.
Controller board
Controls the printing operation based on the communication with the RIP controller and optional peripherals. It also
controls the fuser, toner dispensing, sensor switch feedback, drive motors, clutches and solenoids.
Appendix C: Theory of operation
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