Ribbon/Media Sensor - Intermec EasyCoder 301 Service Manual

6.4 Ribbon/Media
Sensor
WARNING!
Before removing the electrics
cover, turn off the printer and
disconnect the power cord. High volt-
age wires and circuits inside.
1
/. Not in the LinerLess model.
Intermec EasyCoder 301 – Service Manual Ed. 3
Description
The ribbon/media sensor is a module contains three different
sensors; one detects out of ribbon conditions
detect gaps and black marks in the paper web. The latter functions
are described in chapter 7.5.
The out-of-ribbon sensor consist of a infra-red light-emitting diode
(LED) and an optical sensor. A beam of light is directed from the
LED up against the bottom of the printhead bracket, where it is
reflected back and can be detected by the optical sensor.
• If the beam is not detected (e.g. because the ribbon blocks the
beam), a ribbon-present condition is assumed
• If the beam is detected, an out-of-ribbon condition is assumed.
• When the printer is set up for thermal transfer printing, a ribbon-
present condition must be indicated or an error will occur
• When the printer is set up for direct thermal printing, an out-of-
ribbon condition must be indicated or an error will occur.
Note that a faulty or dirty sensor may indicate a ribbon-present
condition even during direct thermal printing and give a "Ribbon
fitted" error message
The sensor is connected to connector J7 on the CPU board and fitted
to the centre-line wall by means of two snap-locks.
Replacement
• Remove the electrics cover as described in chapter 2.3.
• Disconnect the cable from connector J7 on the CPU board.
• Remove the stepper motor as described in chapter
• Remove the printhead as described in chapter
• Disengage the snap-locks and pull out the sensor through the
media compartment. Be careful not to damage the cable!
• Fit a replacement sensor and reassemble the printer in reverse
order. Note that the sensor's cables should run under the belts and
the stepper motor.
Chapter 6 Transfer Ribbon Mechanism
1
.
This Side Up!
Snap-locks
1
and the other two
1
.
1
.
7.3.
7.6.
22