UBI EasyCoder 601 XP – Service Manual Ed. 1
51
Chapter 8 Print Unit
8.6 Label Stop Sensor,
cont'd.
Var. Length Strip and Fix Length Strip:
The light is emitted from the upper sensor and received by the lower
sensor. The beam will either be blocked by the paper or be
completely uninterrupted when the printer runs out of paper . The
firmware assumes an out-of-paper condition if the light has not been
interrupted within a paper feed corresponding to 150% of the set
length (Setup\Media\Media Size\Length).
In case of “variable length strip”, the printer will feed out an extra
195 dots of paper after the last dot of the print image to allow the strip
to be torn off. Note that the print image may contain “invisible” dots,
such as the “white” parts of a character cell or an image, or a space
character.
General:
The information on where the gaps or marks are presently posi-
tioned relative the LSS (and thereby also relative the dot line on the
printhead) is saved as an “invisible” file in the flash memory's file
operating system (see chapter 15.2). However, if the printhead is
lifted, or if the power is interrupted during printing, this file may be
cleared
1
, which will affect any labels between the LSS and the dot
line. In this case, perform a TESTFEED operation.
The LSS checks for gaps or marks at every dot of positive paper feed
(feed out/print), but gaps or marks are ignored at negative paper feed
(pull back). Gaps and black marks up to 256 dots (21.3 mm/0.84")
are allowed.
Adjustment of the Sensitivity
The LSS should always be adjusted when the user changes to
another brand (sometimes even batch) of media, and when a
defective sensor has been replaced. This is especially the case with
self-adhesive labels on backing paper, since the transparency of the
backing paper may vary and the difference between labels and gaps
may be too small. Before starting the adjustment, check that both the
upper and lower sensor are clean and free from obstructions and that
the paper guides are adjusted so as to guide the paper web with a
minimum of play. Also check that the LSS is laterally positioned so
as to detect the gaps or black marks, whenever such media are used.
As standard, there are four means of adjustment for the LSS:
• Performing a TESTFEED by simultaneously pressing the “Shift”
and “Feed” keys in the Immediate Mode.
• Selecting the TESTFEED option in UBI Shell.
• Selecting the TESTFEED option in the Setup Mode.
• Executing a TESTFEED statement in a UBI Fingerprint pro-
gram.
The printer feeds out 1.5 times the set label length while testing all
levels of the LSS at each millimetre of paper feed. The LSS is
adjusted according to the result of the check and a full label is fed
out in accordance with the present feedadjust setup.
The label stop sensor/black mark sensor can be turned off for a
specified amount of paper feed by means of the LBLCOND
statement, see UBI Fingerprint
≥
7.11 Reference Manual.
1
/. It is possible to decide if the paper feed
data will be cleared or not when the
printhead is lifted by means of the UBI
Fingerprint instruction SYSVAR(28). By
default, the paper feed data are not cleared.
