Xerox Phaser 4600 Service Manual page 386

Sensors in the Media Path
Figure 3 shows the location and designation of sensors located in the media path. Error detec-
tion is based on media transport timing through the sensing area.
Table 1 briefly describes the type and function of sensors and switches used to determine
operational status and detect jams or failures.
Table 1 List of Sensor and Interlock Functions
Number Name Type
S1 No paper Photo-receptive
S2 Registration Photo-receptive
S3 Feed Photo-receptive
S4 Exit Photo-receptive
S5 Stack Full Photo-receptive
S6 Duplex Photo-receptive
S7 No paper Photo-receptive
S8 ADC Photo-reflective
S9 Duplex Photo-receptive
S10 Rear Door Microswitch
S11 Port open Photo-receptive
S12 Top Door Microswitch
S13 Size Switch Microswitch
S14 Pick Photo-receptive
S15 Level Photo-receptive
S16 Environmental pcb
S17 Internal temp Thermistor
Media Size Sensing
Trays 2 and optional feeders detect media size using an array of microswitches (Size Switch)
mounted in the tray cavity. When the tray end guide is adjusted, the guide changes the Size
Switch actuator positions. Actuating different combinations of the Size Switch produces differ-
ent combinations of high and low signals. These signals identify what size media is loaded and
what to display on the Control Panel. Also, actuation of the Size Switch signals the tray is
present and closed to the MCU Board.
Media Present Sensing
When the last sheet is fed from any tray, the No Paper Sensor actuator drops to block the No
Paper Sensor. Feeding is inhibited until media is loaded into the tray.
Media Level Sensing
As media is fed from the tray, the media level drops. When the level reaches a certain point, an
actuator unblocks the Stack Height Sensor signaling the control logic to raise the tray bottom plate
with the Lift Motor. Raising the tray bottom plate pushes media up to achieve optimum force
against the Nudger Roller and blocks the Stack Height Sensor resuming paper feed. This loop contin-
ues until the No Paper sensor is activated. Paper level sensing operates the same way for
Trays 2 through 6. Tray 1 uses No Paper sensing only.
8 Principles of Operation
Sensors
Function
Signals no media remaining in Tray 2
Signals leading edge at registration
Signals leading edge registered
Signals media present at exit
Signals output tray full
Signals media present
Signals no media remaining in Tray 1
Monitors Toner density
Signals media present (leading edge)
Signals Rear Door open
Signals Waste Toner Cartridge installed
Signals Top Door open
Signals media size in tray
Signals Pick Assembly position
Signals lift motor to raise tray bottom
Monitors temperature and humidity
Monitors internal temperature
Tray 2
04/2016
8-6
Figure 3 IOT Sensors
Phaser 4600/4620/4622 Printer Service Manual
Revised