Ricoh FW780 Service Manual page 234

ELECTRICAL COMPONENT DESCRIPTIONS
Name
Printed Circuit Boards
Main
PSU
AC Drive
FL Regulator
Operation Panel
Original Feed Drive
(A252 only)
Lamps
Exposure
Fusing
Pre-Transfer (PTL)
Quenching (QL)
Power Packs
Charge/Bias/
Grid Power Pack
Transfer/Separation
Thermistors
Hot Roller
Pressure Roller
Thermofuses
Fusing
Heaters
Anticondensation
Others
Total Counter
Circuit Breaker
(Europe, Asia)/
Fuse (U.S.A.)
A251/A252
Controls all copier functions both directly and
through other PCBs.
Converts the AC voltage to DC voltage.
Provides AC power to the fusing lamp and PSU.
Stabilizes power to the exposure lamp.
Control the operation panel display.
Controls the rotation of the original feed motor.
Provides light to reflect the original's image onto
the drum (fluorescent lamp).
Provides heat to the fusing unit.
Reduces the charge on the drum surface prior to
image transfer.
Neutralizes any charge remaining on the drum
surface after cleaning.
Provides high voltage power for the charge
corona, charge grid, and development bias.
Provides high voltage power for the transfer
corona and separation.
Monitors the hot roller's surface temperature.
Monitors the pressure roller's surface
temperature.
Protects against fusing overheat.
Keeps moisture from forming inside the copier
(option).
Keeps track of the total length of copies made
(Europe) or the total copies made (U.S.A.).
Guards against voltage surges in the input power.
1-8
Function Index. No.
22
21
15
23
10
46
2
3
20
1
19
16
8
11
9
13
28
14
SM