Auto Purge Spacing Guidelines - Dover markem-imaje 5200 Service Manual

SECTION 3 Care and Cleaning
2.1.2
3–4

Auto Purge Spacing Guidelines

The Auto Purge feature is used to periodically purge the specified
printhead without pressing the purge button. Set from the Machine
Setup menu, an auto purge is triggered by the software and the
duration is typically shorter than a regular purge.
NOTE: Specific setup instructions for the Auto Purge parameter can
be found in the Installation and Setup Guide (0855848).
When the printhead is purged, a small amount of ink is forced out of
the jets. Based on line speed, time must be allowed for purged ink to
flow away from the jets, which is the minimum spacing required
between prints. The top jets will clear first, as the ink flows from the
top to the bottom. Jobs created using the upper jets will, therefore,
recover sooner.
NOTE: Do not use the Auto Purge feature with the down jetting
position.
The distance required between prints should be calculated so the
purge cycle does not interfere with printing. Missing or partial prints
can occur when insufficient time is allowed after an auto purge.
Table 3-1 provides guidelines for determining minimum distances.
Use this information as a starting point and modify as needed.
Purge Duration is the length of time that a purge lasts.
Purge Cycle Time is the time required for the printhead to be ready
for the next print and includes time for the array to be cleared of ink.
A purge cycle takes 2.75 - 4.25 seconds, depending on the duration
of the purge.
To calculate the minimum spacing between prints:
Purge Cycle Time = (Purge Duration x Line Speed) / 60 Sec.
Example:
0.3 Sec. Purge Duration, 25m/min Line Speed
(3.625 Sec. x 25m/min) / 60 = 1.51 meters minimum spacing
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