HP LaserJet Enterprise M552 - Page 10

Low-voltage power supply functions ............................................................................. 20
High-voltage power supply ............................................................................................................... 20
High-voltage power supply circuits ................................................................................ 21
Fuser bias ........................................................................................................................ 22
Fuser control ..................................................................................................................................... 22
Fuser circuits ................................................................................................................... 22
Fuser control functions ................................................................................................... 24
Fuser temperature control ............................................................................................. 24
Fuser heater protection .................................................................................................. 26
Fuser unit life detection .................................................................................................. 26
Fuser identication ......................................................................................................... 26
Engine laser/scanner system .............................................................................................................................. 27
Laser/scanner failure detection ........................................................................................................ 28
Safety ................................................................................................................................................ 28
Image-formation process ................................................................................................................. 29
Step 1: Pre-exposure ...................................................................................................... 35
Step 2: Primary charging ................................................................................................ 35
Step 3: Laser-beam exposure ......................................................................................... 36
Step 4: Development ...................................................................................................... 36
Step 5: Primary transfer ................................................................................................. 37
Step 6: Secondary transfer ............................................................................................. 37
Step 7: Separation ........................................................................................................... 38
Step 8: Fusing .................................................................................................................. 38
Step 9: ITB cleaning ......................................................................................................... 39
Step 10: Drum cleaning ................................................................................................... 39
Toner cartridges ................................................................................................................................ 40
Design ............................................................................................................................. 40
Memory chip .................................................................................................................... 42
Toner seal ........................................................................................................................ 42
Toner level and cartridge life detection .......................................................................... 42
Developing unit engagement and disengagement control ........................................... 42
Cartridge Authentication Technology (CAT) ................................................................... 43
Authentication .............................................................................................. 44
Anti-theft ...................................................................................................... 44
Intermediate transfer belt (ITB) unit ................................................................................................. 45
Primary-transfer roller engagement and disengagement control ................................ 45
ITB unit detection ............................................................................................................ 47
ITB cleaning mechanism ................................................................................................. 48
Secondary transfer roller functions ............................................................................... 48
Calibration ....................................................................................................................... 49
Pickup, feed, and delivery system ....................................................................................................................... 50
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