2. Operationa. Turning On and OffWhen the main motor drive signal (M1ON) goes ‘1’, the phase comparison circuit andthe frequency circuitry shown in Figure 2-107 send control signals.The control signals from both circuits are combined and sent to the motor drivecircuit, turning on the motor drive circuit and rotating the main motor.When M1ON goes ‘0’, on the other hand, the output of the control signal stops andremains so, keeping the motor stationary.b. Controlling to a Specific SpeedThe rotation of the machine’s main motor is controlled to a specific speed.The reference signal generating circuit on the motor control PCB generatesreference pulses which are sent to the phase comparison circuit and the frequencycomparison circuit.The phase comparison circuit generates control signals (phase comparison signals)so that the phase of the clock pulses (MMCLK) from the main motor matches that of thereference signals.Likewise, the frequency comparison circuit generates control signals (frequencycomparison signals) so that the frequency of the clock pulses (MMCLK) from the mainmotor matches that of the reference pulses.After both phase comparison signal and frequency comparison signal have beencombined, they are sent to the motor drive circuit for control of the power to the mainmotor, thereby keeping the revolution to a specific number.3. Detecting an ErrorWhen an excess load is imposed on the motor for some reason, the DC controllerPCB will detect a fault in the clock pulses from the main motor and, as a result, willindicate ‘E010’ and an error message on the control panel.COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV.0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 2 BASIC OPERATION2-12
