Oki ML420 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
• Characters less than 38ips
Mode
1
2
3
4
5
6
7
• Only Image
Mode
1
2
3
4
5
6
7
• When the temperature is between 118°C and 125°C, the mode switches sequentially
to higher level. When the temperature falls below 116°C, the mode switches to lower
level.
• When the temperature exceeds 125°C, printing will stop.
• When temperature gradient is steep, higher mode shall be specified directly.
42113901TH01 Rev.3
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% 1
13% 100% 2
9% 80% 2
5% 50% 2
0% Stop –
Stop
Mode up
Mode down
• Characters more than 38ips
Mode DUTY PrintSpeed
1 100% 100%
2 87% 85%
3 30% 70%
4 13% 55%
5 9% 40%
6 5% 30%
7 0% Stop
Oki Data CONFIDENTIAL
125°C
118°C
116°C
Pass
1
1
1
1
1
1
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