I
WARN ING WAR
ATTENTION
Hot
B
I
F
5 I
9
C
I
4
(a) Back of the
D
3 II
C 5 C 6 7
1 5 2 2 2 3 1 8 1 0
(b)
connectors closeup
Figure 5-5.
Connectors F and R Wiring
Table 5-6. Relationship between Common Wires
and Each Coil
F
R
Common Corresponding Common Corresponding
Line
Coil Numbers
Line
Coil Numbers
c l
1, 9, 17
C5
2, 7, 15
C2
5, 13, 21
C6
3, 11, 19
C3
12, 20, 24
C7
14, 22, 23
25
C4
4, 8, 16
C8
6, 10, 18
I
I
I
I
I
I
–
r
-
-
-
-
-
-
-
I
4.3
5 0
Thermistor Resistance Value
Figure 5.6, Relationship Between
Temperature and Thermistor Resistance
If a specific dot is not printed, one possible cause is a defective
coil (refer to Figure 1-2 for
the relationships between the coil numbers and wire pins).
Whether the coil is defective or not is determined by measuring the resistance across the terminals
of the common line and corresponding coils (refer to Figure 5-5 and Table 5-6). The normal resistance
for a
coil is 8.6 + 10% (at
If a thermistor, a temperature sensor in the
is shorted, the message “HEAD HOT” is displayed
on the LCD even when printing is not being executed. The relationship between the
temperature and thermistor resistance value in the normal state is shown in Figure 5-6.
5-16
Summary of Contents for LQ-2550
Page 1: ...L Q 2 5 5 0 TECHNICAL MANUAL EPSON ...
Page 240: ...REV A P r cl Figure 6 3 LQ 2550 Lubrication and Adhesive Application Points Diagram 2 6 3 ...
Page 241: ...REV A 7 i_ Figure 6 4 LQ 2550 Lubrication and Adhesive Application Points Diagram 3 6 4 ...
Page 252: ...REV A I 1 I 7 v m o m x b Figure A 6 PPD781OHG Block Diagram A 7 ...
Page 297: ...REV A 1 L I Irl N I i t 1 I I x Figure A 50 ROPSE Board Circuit Diagram A 52 ...