REV.-A
The
VDC line has a voltage overload protection circuit and a voltage drop protection circuit. The
V voltage overload protection circuit cuts the supply if the voltage reaches or exceeds 36 VDC.
It stops switching circuit operation, which stops the output of the
VDC line. The voltage drop
protection circuit protects the printer from damage that might occur if the secondary circuitry of the
VDC line short circuits. If a voltage drop is detected, it stops switching circuit operation, which
stops the output of the
VDC line.
P o w e r S u p p l y B o a r d
P r i m a r y
Secondary
I
Full wave
q
C i r c u i t
AC Input
II
I
line
V o l t a g e
O v e r l o a d
I
P r o t e c t i o n
I
I
C i r c u i t
I
I
I
I
I
I
I
V o l t a g e
O v e r l o a d
I
I
P r o t e c t i o n
I
C i r c u i t
I
I
V D C
- - - - - - - - - - - - - - - -
I
I
Power
Switch
Figure 2-16. Power Supply Circuit Block Diagram
2 - 1 3
Summary of Contents for LQ-1170
Page 1: ...LQ 1170 24 PIN DOT MATRIX PRINTERS TM LQ8 1170 ...
Page 2: ...L Q 8 7 0 1 1 7 0 SERVICE MANUAL EPSON T Printed on recycled paper ...
Page 101: ...10 9 91 Yes NO Replace pluggable chips on main board 5 6 ...
Page 110: ...Table 5 4 Repair of the Power Supply Board Continued 5 15 ...
Page 118: ......
Page 121: ...REV A Figure 6 2 LQ 870 Lubrication Points 6 3 ...
Page 122: ...REV A Figure 6 3 LQ 1170 Lubrication Points 6 4 ...
Page 134: ...1 I II ...
Page 135: ...REV A Q m u D w IL 0 1 xl Figure A 3 CO60 DRV Board Circuit Diagram A 11 ...
Page 136: ...Figure A 4 CO60 PSB Board Circuit Diagram A 12 ...
Page 138: ...LO SLOE002 OWO9 1Nd 0 9 0 3 5 f l P I 11 I 01 I 6 I 8 1 L 9 I 9 I B I I2 I 2 I 1 ...
Page 142: ...REV A Fl 24ov T3 IsA I I II II AL I CU rl Figure A 10 C060 PSE Board Component Layout A 1 8 ...
Page 143: ...LMS d10 IP IMS dla ...
Page 144: ...REV A A 4 EXPLODED DIAGRAM Figure A l 2 1 Exploded Diagram for LQ 870 A 2 0 ...
Page 145: ......
Page 146: ...REV A Figure A 13 1 Exploded Diagram for Model 5DlO A 22 ...
Page 147: ... 5 2 5 610 c 3 5 9 0 El ...
Page 149: ...REV A A 5 CASE OUTLINE DRAWING Figure A l 4 1 Case Outline Drawing for LQ 870 A 25 ...
Page 151: ...lllllll IllI l l IIIIII II0 IIll III1 I I I C O 6 1 M A I N B o a r d A 3 7 ...
Page 152: ... U nRonenl2 i i C O 6 0 HAIN B t _1 m r OL J IIA IS I 19 CNI 36 I I8 I 23 IS ...
Page 153: ...a i iJ 0 E fig tfti I z ...