Xerox 8500DN Service Manual - Page 54

Theory of Operation I/O Board Sensors All sensor and switch readings are input into the I/O Board. The I/O Board translates these states into encoded information that it sends over a serial data bus (I/O Board data cable) to the Electronics Module. The Electronics Module has no direct connection to sensors, switches, or solenoids. In order to activate a clutch or solenoid, the Electronics Module sends a command to the I/O Board, which processes the command and activates the appropriate device. Sensors throughout all the major subsystems provide indicators of vital print operations. The following graphic identifies the location of the printer's sensors. Strip Sensor Exit Door Sensor Ink Out Ink Low Paper Exit Sensor Drum Temperature Sensor Preheater Sensor Deskew Sensor Media Width Sensor Tray Empty Sensor (Also in Trays 3 & 4) Drum Position Encoder Front Door Sensor Paper Size Sensor Pick Sensor (525-sheet Feeder) Tray Lift Sensor (Also in Trays 3 & 4) s8500-023 2-22 Phaser 8400/8500/8550/8560 Color Printer Service Manual