Canon CLC 1120 Service Manual page 59

a. Turning On/Off the Main Motor
When the DC-CPU on the CPU PCB causes the main motor drive signal (MNMON) to go '1'
through the DC driver PCB, the control circuit on the main motor driver PCB generates drive
current to rotate the main motor at a specific speed.
When the drive signal goes '0', on the other hand, the output of the control signal stops,
removing the drive current and, thus, stopping the main motor.
b. Controlling the Rotation to a Constant Speed
When the main motor rotates, its speed is detected and communicated to the rotation speed
control circuit, which in response compares the speed against pulse signals and exerts control so
that the phase of one matches that of the other. At this time, a signal (MNMRDY), used to indicate
a state of constant speed, is sent to the CPU PCB.
Related Error Code
E010
If an error causes the rotation speed of the motor to deviate, the main motor ready signal (MNMRDY)
goes '0', causing all copier operations to stop (main motor error).
COPYRIGHT © 1999 CANON INC. CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 2 BASIC OPERATION
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