3. Remedying the cause. Replace any set of thermistors that does not have a good
match among all three. If a second set of thermistors causes another overfill, remove
that set and swap it with another set that is not causing overfills. If the problem re-
mains with the original color channel (i.e., the overill does not follow the thermistors),
then the headboard can be suspected.
Jetting
Jets out clustered at front of printhead, all colors affected: this generally signals that
the wiper head in the service station is not reaching the front of the printheads. An
out-of-calibration service station or service station wiper rails that have a build-up of
ink on them will prevent proper wiping. Remove the enclosure, clean and regrease
the rails (use P/N 0900854), recalibrate, and test.
Vacuum-related problems: either too much vacuum or not enough vacuum applied to
the printheads can cause jet drop-out during printing. Too much vacuum inhibits the
flow of ink from the reservoir to the jets. Cancel a print and quickly inspect the orifice
plates. If dry, there may be too much vacuum (a Warning on the control panel should
also be present in such a case). If the orifice plates are wet with ink, there may be
insuffcient vaccum. Ink is drooling out of the jets and pooling on the orifice plate.
This inhibits the jetted drops from exiting the printhead. Check for leaks in the sys-
tem from printhead all the way back to the vacuum assembly. Clean or replace the
vacuum restrictor and replace the vacuum air filters. There is also a vacuum trouble-
shooter built in to the control panel; use this tool to help isolate leaks.
5400 Technical Training Manual
MacDermid ColorSpan Confidential
Page 36 of 39
MacDermid, Inc. 11311 K-Tel Drive, Minnetonka, MN 55343
Phone: 952-944-9457 Fax: 952-944-8507
