Canon iR1600 Series Service Manual page 260

CHAPTER 8 EXTERNALS AND AUXILIARY CONTROL SYSTEM
4.2 Control
4.2.1 Controlling the Speed
The machine's heat discharge fan (FM101) is subjected to 2-speed control (full-speed and
half-speed) as follows:
[1] Full-Speed Control
When the ASIC on the DC controller PCB causes the fan ON signal (FANON) to go '1'
and the fan full-speed rotation signal (FANFULL) to go '1', the drive voltage control
block supplies fan drive voltage (FANDRV) of +24 V to rotate the heat discharge fan to
rotate at full speed.
[2] Half-Speed Control
When the ASIC on the DC control PCB causes the fan ON signal (FANON) to go '1'
and the fan full-speed rotation signal (FANFULL) to go '0', +16V fan drive voltage
(FANDRV) is supplied to rotate the heat-discharge fan at half speed.
DC controller PCB
ASIC
CPU
8-10
COPYRIGHT© 2002 CANON INC.
+24V
FANFULL
Drive voltage
FANON
control block
F08-402-01
FANDRV
FANLOCK*
2000 CANON iR1600/iR2000/iR1610/iR2010 SERIES REV.0 MAR. 2002
Heat discharge fan
J106
(FM101)
15
16
14