Table of contents 1 Theory of operation Basic operation ..................................................................................................................................... 2 Major product systems ......................................................................................................... 2 Product block diagram ......................................................................................................... 2 Sequence of operation ......................................................................................................... 3 Normal sequence of operation ............................................................................
3 Formatter-control system ..................................................................................................................... 5 Sleep mode .......................................................................................................................... 5 Input/output .......................................................................................................................... 5 CPU ..................................................................................................................................... 6 Memory ................................................................................................................................
6 Firmware ............................................................................................................. 6 Nonvolatile memory ............................................................................................ 6 PJL overview ....................................................................................................................... 6 PML ..................................................................................................................................... 6 Control panel .......................................................................................................................
6 Engine-control system .......................................................................................................................... 7 DC controller ........................................................................................................................ 8 Motors ............................................................................................................... 11 Fans .................................................................................................................. 13 Fuser-control circuit ...........................................................................................
14 Fuser temperature control ................................................................ 15 Fuser protective function .................................................................. 16 Fuser failure detection ...................................................................... 17 Low-voltage power supply ................................................................................. 18 Overcurrent/overvoltage protection .................................................. 20 High-voltage power supply ................................................................................
21 Laser scanner system ........................................................................................................ 23 Laser failure detection ....................................................................................... 24 Image-formation system ..................................................................................................................... 25 Electrophotographic process ............................................................................................. 25 Image formation process ...................................................................................................
27 Latent-image formation block ............................................................................ 28 Pre-exposure .................................................................................... 28 ENWW iii