Ribbon End Sensor - Intermec EasyCoder 501 Service Manual

7.4 Ribbon End
Sensor
Intermec EasyCoder 501 – Service Manual Ed. 7
The ribbon end sensor is a photoelectrical device that detects
whether there is any thermal transfer ribbon in the printer or not. It
is fi tted to the center section immediately behind the print mecha-
nism by means of a single #T10 Torx screw. The sensor assembly
consists of a sensor with cable and connector, and a combined
mirror/bracket.
Bracket
The ribbon end sensor works like this. A narrow beam of light is
emitted from the sensor and is either absorbed by the black transfer
ribbon, or refl ected back by a mirror to a receiver in the sensor. The
fi rmware compares the signal from the sensor with the printer's
setup in regard of media type in order to avoid printing on the
wrong type of media:
Set up
Thermal transfer media
Thermal transfer media
Direct thermal media
Direct thermal media
If the printer is not fi tted with a thermal transfer mechanism,
the ribbon end sensor must be disabled by a strap on P-9; pin
J1 on the CPU board. This strap also excludes any thermal
transfer media options from the setup. Obviously, if the
printer is fi tted with a thermal transfer mechanism, such a
strap must be removed.
The ribbon end sensor is connected to P-603 on the CPU
board.
Chapter 7 Transfer Ribbon Mechanism
Sensor
Mirror
Detection Error
Ribbon OK
No ribbon Error 1027 Out of transfer ribbon
No ribbon OK
Ribbon Error 1058 Transfer ribbon fi tted
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