CognitiveTPG A776 - Manual (Page 38)

A776 UG00001 B 10/06 A776 Two-Color Thermal/Impact Hybrid Printer: User Guide
33 Chapter 4: Using the Printer
Tips for Avoiding Problems
Prevent overheating of the print head
Overheating of the thermal print head is one of the most common causes of printer problems. To avoid overheating do
one or more of the following:
Reduce the amount of solid coverage when printing receipts.
Reduce the time of continuous printing, or the “duty cycle.” The duty cycle is the percentage of time that the
printer can be actively printing in any sixty-second period of time. The duty cycle will vary for your printer
depending on the temperature of the room where you have set it up and the amount of print coverage, and it
is expressed as a percentage in the table below. For example, if the duty cycle is 50 percent, it means that the
printer should only print for 30 seconds out of every minute. If the duty cycle is 25 percent, the printer should
print for 15 seconds and then be idle for another 45 seconds.
Reduce the temperature of the room where you put the printer. Keep in mind that the temperature may also be
affected if the printer is exposed to direct sunlight, near a space heater or heat lamp, and so on. 1.
2.
3.
CAUTION
If the duty cycle exceeds the limits shown in the table below, the receipt print head will heat up and shut down. This
may damage the print head.
Allowable duty cycle (measured over one minute of continuous printing)
Avoid Harsh Environments
The A776 printer is a durable piece of equipment and can withstand a range of physical environments. However, the
printer’s internal mechanical components are vulnerable to dust and airborne chemicals, particularly in places like
home improvement stores, garden shops, and warehouses. In these kinds of environments you will need to make sure
that your printer is cleaned regularly to make sure it keeps working properly.
To prolong the life of your printer, we recommend regularly inspecting and cleaning the MICR read head, sensors,
carriage shaft and printer mechanisms.
Paper
CAUTION
Use of paper other than that approved by TPG can damage the printer and void all warranties.
MICR heads
CAUTION
Make sure you don’t insert a check into a printer with a paperclip or staple attached!
For reference:
A typical receipt with text (contains some blank
spaces) is approximately 12% dot coverage.
A full line of text characters (every cell on the line
has a character in it) is approximately 25% dot
coverage.
Graphics are approximately 40% dot coverage.
Barcodes are approximately 50% dot coverage. •
•
•
•
A solid black line is 100% dot coverage.
“Duty cycle “ is the percentage of time that the
specified “Amount of solid coverage” can be printed
during a one minute period of time.
Example: at 20% solid coverage, 35° C temperature, a
50% duty cycle is to be used, resulting in 30 seconds of
printing and 30 seconds without printing.
•
•
Ambient temperature
25°C 35° C 50° C
Amount of solid coverage (77°F) (95°F) (122°F)
20% 100 % 50 % 20 %
40% 50 % 25 % 10 %
100% 20 % 10 % 4 %