Speed Control - Canon imageRUNNER 330 Service Manual

CHAPTER 10 EXTERNALS/AUXILIARY MECHANISMS
B. Sequence of Operations

1. 2-Speed Control

Of the fans used in the machine, some are designed to rotate at half speed during standby
(Tables 10-201, -202 through -204). The speed is switched between full and half by changing the
voltage supplied by the DC-CPU* to the fans.
* CPU for the DC controller circuit (mounted on the image processor PCB).
Speed Timing
Full Copying
Half Stanby
DC-CPU
Image processor
PCB
10-6
COPYRIGHT © 1999 CANON INC. CANON imageRUNNER 400/330 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Supply voltage
+24V Composite power
supply PCB
+15V Low-voltage power
supply PCB
From composite
power supply
+24V
PORT A
Voltage switching
PORT B
circuit
DC controller PCB
Figure 10-204
Supply source PORT A
From low-voltage
power supply
+15V
24V or 15V
FM-LCK
0V
PORT B
1 0
0 1