Appendix B - Alignment Management; Ticket Alignment; Enabling, Calibrating And Setting Of Parameters - Custom Engineering VKP80II User Manual

B.1 TICKET ALIGNMENT
B.1.1 Ticket alignment
Paper with an alignment notch can be used in order to handle tickets with pre-printed fi elds and a fi xed
length.
To guarantee the alignment it is necessary that the "Notch Alignment" parameter is enabled from the key
setup (see setting confi guration parameters), that the alignment sensor is calibrated and that the parameters
are set.
The calibration of the sensor occurs automatically within the printer setup.
B.1.2 Enabling, calibrating and setting of parameters.
The notch sensor is a refl ection sensor that emits a band of light and detects the quantity of light refl ected to
it.
The presence of the notch is therefore detected by the amount of light that returns to the sensor, taking into
account that the light is refl ected by the white paper and absorbed by the black.
Calibration of the sensor occurs automatically and consists in adjusting the quantity of light emitted to adapt
it to the degree of whiteness of the paper used.
To start self-calibration, the "Notch Alignment" parameter will have to be enabled from the printer setup (see
setting confi guration parameters):
Notch Alignment
The printer will perform some paper FEEDS, at the end of which it will print the value settings, for example:
Autosetting Notch
Threshold White
The "Autosetting Notch" parameter indicates the operating condition of the self-calibration process; OK will
appear if it has been successful, but if it has failed the words NOT OK will appear.
In this case the default parameters concerning the "Threshold White" parameter will be set.
The "Threshold White" parameter indicates the power-up level of the sensor emitting side; its value ranges
from 0V to 5V with the corresponding value appearing as a percentage (from 0% to 100%).
Another parameter that needs to be set is the threshold:
Notch Threshold..
It is used to detect the presence of the notch: if the voltage value read by the sensor exceeds the threshold
value set the notch is identifi ed, otherwise the white paper is considered.
In order to better identify the optimum threshold for the paper being used, a paper characterisation function is
also available in setup.
Characterize Paper.
By activating this parameter the outgoing voltage of the sensor will be presented in a graphic form as shown
in fi gure B.1 below:

APPENDIX B - ALIGNMENT MANAGEMENT

: Enabled
: OK
: 1.9V [39%]
: 3.0V
:Yes
VKP80II B-1
User Manual