Oki ML490 Maintenance Manual page 28

(4) Overheat alarm
(a) Head overheat alarm
The voltage of the output HTEMP signal of the thermistors, one of which is contained
in the print head and the other in the SP/LF driver, is monitored by the A/D port of
the MPU to control the voltage.
Temp
• Mixing Image and Characters
Mode
1
2
3
4
5
6
7
• Only Image
Mode
1
2
3
4
5
6
7
• When the temperature is between122 C and 132 C, the mode switches sequentially
to higher level. When the temperature falls below 118 C, the mode switches to lower
level.
• When the temperature exceeds 132 C, printing will stop.
• When temperature gradient is steep, higher mode shall be specified directly.
42114101 Rev.1
Mode and print control
DUTY PrintSpeed Pass
100% 100% 1
87% 100% 1
30% 100% 1
13% 90% 1
9% 80% 1
5% 70% 1
0% Stop —
DUTY PrintSpeed Pass
100% 100% 1
87% 85% 1
30% 70% 2
13% 55% 2
9% 40% 2
5% 30% 2
0% Stop —
Stop
Mode up
Mode down
Direction Stop Printing
--- Until restoration
Direction Stop Printing
--- Until restoration
132 C
122 C
118 C
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