HP OFFICEJET PRO X476

Table of contents
1 Theory of operation ........................................................................................................................................ 1
Basic operation ..................................................................................................................................... 2
Function structure ................................................................................................................ 2
Operation sequence ............................................................................................................ 3
System control ...................................................................................................................................... 6
Formatter and data path ...................................................................................................... 6
Engine control ...................................................................................................................... 7
Pen interface (I/F) ................................................................................................................ 9
Power supply ..................................................................................................................... 10
Print subsystem .................................................................................................................................. 11
Printbar .............................................................................................................................. 11
Printbar air management system ....................................................................................... 13
Printbar lift .......................................................................................................................... 13
Ink cartridges ..................................................................................................................... 13
Optical scan carriage ......................................................................................................... 13
Print system operational states .......................................................................................... 13
Paper-handling system ....................................................................................................................... 16
Input trays .......................................................................................................................... 21
Paper path zones ............................................................................................................... 22
Servicing system ................................................................................................................................ 26
Service sled ....................................................................................................................... 27
Transmission system .......................................................................................................................... 28
Components ...................................................................................................................... 29
States ................................................................................................................................. 29
Aerosol management system ............................................................................................................. 31
Document feeder ................................................................................................................................ 33
Document feeder operation ............................................................................................... 33
Document feeder paper path and sensors ........................................................................ 33
Document feeder jam detection ......................................................................................... 34
Scanner system .................................................................................................................................. 35
Scanner power-on sequence of events ............................................................................. 35
Copy or scan-to-computer sequence of events ................................................................. 36
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