REV.-A
PRINCIPLES OF OPERATION
2.2.3 RECTIFIER AND SMOOTHING CIRCUIT
The AC IN voltage from the filter circuit is full-wave rectified by diode bridge DB1, and converted to approx-
imately 2 x AC IN voltage by smoothing capacitor C7. The + 24 VDC, + 5 VDC, and ± 12 VDC voltages
are converted from this DC voltage.
DB1
NOTE:
The item in parentheses pertains to the 220/240 V version
Figure 2-19. Rectifier and Smoothing Circuit
2.2.4 STARTING CIRCUIT (MAIN SWITCHING CIRCUIT)
Figure 2-20 shows the starting circuit. The operation sequence is as follows.
(1) When the main power source is connected, the AC input passes through the input filter and is then rec-
tified and smoothed. The resulting DC voltage V
IN
is input into the circuit.
(2) VIN is applied to starting resistance R7 and passes through point A. Base current lB flows through tran-
sistor Q1, causing the transistor to conduct.
(3) At the same time,
VI
N
is applied to coil 4-3 of pulse transformer T1, causing a voltage of (7/60T)
(VI
N
)
at 8-2, so that the positive feedback current of switching circuit
I
B
flows in the direction of B. This causes
a sharp rise, and Q1 quickly switches on.
(4) Current
I
L
through coil 4-3 increases linearly over time. During this time, a voltage of (10/60T)
V
IN
is
induced through coils 7-8 and 8-11, and a voltage of (19/60T)
V
IN
through coil 9-10. For all these coils,
then, current attempts to flow in the direction of D; however, this direction opposes the direction of diodes
D22, D23, and D20, so that no current flows through the secondary side of the circuit.
LQ-510
2-15
Summary of Contents for AP-4000
Page 1: ...LQ 510 AP 4000 T E C H N I C A L M A N U A L EPSON ...
Page 4: ...REV A REVISION SHEET iv LQ 510 ...
Page 103: ...REV A PRINCIPLES OF OPERATION LQ 510 Figure 2 68 A D Converter Circuit 2 61 ...
Page 125: ...OPTIONAL EQUIPMENT REV A 3 16 Figure 3 12 Lubrication Points 2 LQ 510 ...
Page 167: ......
Page 192: ...MAINTENANCE REV A L __ w w n Figure 6 3 LQ 510 Lubrication Points 6 3 LQ 510 ...
Page 202: ...APPENDIX REV A Table A 6 E01A05 Pin Functions A 8 LQ 510 ...
Page 212: ...3 L CN 1 ...
Page 213: ...REV A APPENDIX Figure A 25 SANPSE Board Component Layout LQ 510 A 19 ...
Page 214: ...REV A APPENDIX J Figure A 26 SANPSE Board Circuit Diagram A 20 LQ 510 ...
Page 215: ...REV A APPENDIX Figure A 27 SANPNL W Board Circuit Diagram LQ 510 A 21 ...
Page 216: ... w 3 0 4 CN1 14 18 22 I IP I9 3 1 2LSl39 2 6 8 2 4 9 TOM4 BOARD Y 4 5 4 2 0 9 0 0 0 0 0 ...
Page 220: ...h i ...
Page 221: ...REV A APPENDIX 506 Figure 14 32 Model 5710 Printer Mechanism Exploded Diagram A 29 ...
Page 222: ...APPENDIX REV A Figure A 33 C80006 Pull Tractor Exploded Diagram A 30 LQ 510 ...
Page 223: ... Y ...
Page 224: ...APPENDIX REV Figure A 35 LQ 510 Printer Cover A Case Outline Drawing A 32 LQ 510 ...
Page 225: ...APPENDIX REV A J 2 7 J Bl Figure A 36 LQ 510 Printer Cover B Case Outline Drawing LQ 510 A 33 ...
