UBI EasyCoder 501, Техническое руководство

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UBI EasyCoder 501 – Technical Manual
SETUP PARAMETERS, cont'd.
The Detection facilities are used to adjust the label stop/black mark
sensor (LSS) and to control the paper feed.
LSS Adjustment:
The LSS is a photo-electric detection device that controls the paper
feed. Situated inside the printing mechanism, it detects the front
edges of the labels, slits in tickets or tags, or the rear edges of black
marks on the back side of the paper web.
If the printer is set up for “Label (w gaps)”, “Ticket (w gaps)”, “Fix
length strip”, or “Var. length strip”, a narrow beam of light is
emitted from the upper part of the LSS and received by the sensor
in the lower part. Non-transparent paper will block the beam
completely, whereas semi-transparent backing paper between la-
bels will allow some of the light to pass through. A detection gap in
the ticket web causes no interference at all. An out-of-paper
condition is assumed, when no interference to the beam has been
detected within a feed length corresponding to the distance between
the dot line on the printhead and the sensor.
When the printer is set up for “Ticket (w mark)”, the light is emitted
from the lower part of the LSS. The beam can be reflected back to
the receiver by the white paper at the back of the web. If the beam
hits a black mark, practically no light will be reflected back . An out-
of-paper condition is assumed, when no reflected light has been
detected within a feed length corresponding to the distance between
the dot line on the printhead and the sensor.
Obviously, it is important that the printer is set up for the correct type
of media (see “Media Type” later in this chapter) so the firmware
can interpret the signals correctly.
The LSS can be moved max. 50 mm sideways across the web. The
inner edge of the handle indicates the lateral position of the sensor.
The LSS is automatically fine-adjusted when a Testfeed operation
is performed. Moreover, the LSS emitters can be adjusted in regard
of light intensity in the Setup Mode or by means of setup files and
the LSS receiver can be adjusted by means of a potentiometer on the
CPU board (see the chapter “Electronics/Potentiometers”).
If the printer works as expected, there is no need to adjust the LSS,
but if the printer starts to feed out labels or tickets in an unexpected
manner, check that the sensor is properly aligned in relation to the
web and that it has not become dirty. Perform a few Testfeed
operations to allow the sensor to auto-adjust itself.
If the error remains, proceed according to the description of the
Setup Mode for the printer model in question. Only as a last resort
should the potentiometer be adjusted.
Continued!
Detection
• LSS Adjustment
• Feed Adjustment
Emitter and
Receiver
Emitter
The upper part of the LSS is a light emitter
for labels, tickets and strip, whereas the
lower part contains both a receiver and
an emitter for black mark detection.
Handle
The inner edge of the handle indicates the
position of the LSS.
Note!
Printers fitted with a ribbon save device
have different type of label stop/black
mark sensor mechanism, where the
lateral position of the sensor is adjusted
by means of a screw instead of a handle,
see chapter “Ribbon Save Device” later
in this manual.