HP laserjet 3390, 3392 all-in-one Service Manual
Basic operation
This chapter presents an overview of the relationships between major components in the all-in-one, and
includes a detailed discussion of the image-formation system. The following systems are discussed:
includes a detailed discussion of the image-formation system. The following systems are discussed:
●
Engine control system
●
Laser/scanner system
●
Pickup/feed/delivery system
●
Image-formation system
Figure 4-1
HP LaserJet 3390/3392 all-in-one system block diagram
Sequence of operation for the base unit
Operational sequences are controlled by the microprocessor and the DC controller.
Table 4-1
Sequence of operation
Name
Timing
Purpose
WAIT
From power-on until the end of the main-motor initial
drive
drive
Detects the presence of a print cartridge; clears
potential from the drum surface and cleans the
transfer roller
potential from the drum surface and cleans the
transfer roller
for
a complete description of the WAIT (power-on)
period.
period.
STBY (standby) From the end of the WAIT or LSTR period until either
a print command is sent from the formatter or the
power is turned off
power is turned off
Prepares the all-in-one to receive print commands
INTR (initial
rotation)
rotation)
From the time of the print command until the pickup
solenoid is turned on
solenoid is turned on
Prepares the photosensitive drum for printing
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Chapter 4 Theory of operation
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