Lexmark MS310 4514-220, Руководство по обслуживанию

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Trailing edge sensor
Detects the media’s trailing edge as it passes the pick tires. Among other capabilities, this sensor can be used
to determine the paper size sensor and the media stack height.
MPF sensor
Detects the presence of media in the MPF tray.
Media present sensor
Detects the presence of media in the tray.
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.
Capactive Toner Level Sensor (CTLS)
Detects the amount of toner in the imaging unit. If the toner level is low, the cartridge auger motor is triggered
to add toner from the toner cartridge to the imaging unit.
Front door sensor
Is a safety switch that cuts off a 5 V DC supply from the controller board to the LSU to prevent the laser from
activating when the front door is opened.
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.
4514-2xx
Theory of operation
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