Epson LQ-1170 Service Manual page 33

1.6.11 Protection during Heavy Duty Printing
This printer has a protection function to prevent the printhead
when the head driver voltage drops. If the temperature of the printhead exceeds the maximum allowed
value, printing stops automatically. When the printhead
resumes. At first, printing resumes at a lower print speed. However, as the printhead
decreases, print speed increases
to the normal speed. If the printhead
stops printing. The printer stops or resumes printing as the printhead temperature increases or
decreases.
If the voltage supplied to the head drive circuit drops below its minimum limit as a result of heavy duty
printing, printing is interrupted immediately. When the power supply voltage increases to a certain
value, the remaining print line is printed at half speed. this protective action occurs when half or more
of the wires are activated continuously.
temperature drops to a certain value, printing
temperature continues to increase at the lower speed, the printer
1-25
from overheating and to stop printing
REV.-A
temperature