Olivetti XZAC4219-03 PR2 plus, Руководство по обслуживанию, Страница: 67 / 160

4-14 XZAC4219-03
4.3
SETTINGS
4.3.1
CALIBRATION OF THE PHOTOSENSORS
Machine photosensors are calibrated in the production phase. Changes in the electrical characteristics of the
photosensors or the use of particular paper may require further calibration at the customer site.
Machine photosensors that must be calibrated are:
•
“Paper present” photosensors
Consist of two leds and two photo-receivers and are the first to detect insertion of the document in the
front slot. The light beam is transmitted by optical fibers.
•
“Front paper alignment “ photosensors
Housed in the same mechanical unit as the paper present photosensors, indicated in this manual as front
photosensors group.
The front paper alignment photosensors check alignment of the document before this moves close to the
printhead. They consist of four leds and the same number of photo-receivers, all coupled by optical fibers.
•
"Autoborder" photosensor
Is fitted on the printhead and detects the presence of the paper in order to measure the position of the
first print column. This photosensor also permits (if selected from set-up) control of printing interrupt
functions if the paper is narrower than the print line sent by the system.
The position in the machine of the individual photosensors is illustrated in the figure on the next page.