3.4 CHARGE CORONA POWER PACK
The main PCB sends a PWM (Pulse Width Modulation) signal to the charge
corona power pack. According to the PWM ratio, the dc power pack outputs a
high dc voltage to the charge corona wires. The main PCB determines the
PWM ratio based on the process control data.
There is a safety relay (RA303) on the dc drive board which is activated by a
signal from the main PCB. In case of the SC conditions related to the high
voltage devices and the abnormal exposure lamp on, the main PCB turns the
RA303 to cut the power of dc 24 V to the power pack through its contact.
DC Power Supply
Main PCB
DC Drive PCB
Drum Current
Detect PCB
Charge
Corona P.P.
PWM
TRIG
GND
24 V
Door
SW
A171D506.wmf
31 July 1995
DRUM CHARGE
2-21
Summary of Contents for FT8680
Page 3: ...SECTION 1 OVERALL MACHINE INFORMATION ...
Page 8: ...MEMO 31 July 1995 SPECIFICATIONS 1 5 ...
Page 23: ...6 5 IMAGE OVERLAY MODE 2ND SIDE A171V505 wmf PAPER PATH 31 July 1995 1 20 ...
Page 24: ...SECTION 2 DETAILED SECTION DESCRIPTIONS ...
Page 133: ...Timing Chart 1 Stack 2 Paper Feed A171D551 wmf A171D552 wmf 31 July 1995 DUPLEX 2 109 ...
Page 159: ...SECTION 3 INSTALLATION ...
Page 177: ...SECTION 4 SERVICE TABLES ...
Page 229: ...SECTION 5 REPLACEMENT AND ADJUSTMENT ...
Page 362: ...SECTION 6 TROUBLESHOOTING ...