Operating Principles
Rev. A
2-1
Thermistor
Thermistor is attached onto the color printhead to monitor the temperatures around the printhead. It
functions to avoid change in ink viscosity, which affects printing result. The signal output from the
sensor is directly transmitted to the analog port of the .
ASF_PW : Output from the ASF PW (Paper Width) sensor.
The ASF sensor uses a sliding potentionmeter. (The maximum resistance :10kΩ.) It is attached to
the left edge guide in the ASF hopper assembly. By aligning the left edge guide to the paper, the
sensor actuator runs along the grooves at the bottom of the stacker. The length measured by the
actuator is converted into ohms which corresponds to the paper width, then the value is transferred to
the analog port of the . The paper width is detected in 10 ranges between 98 mm and 441 mm.
(See Table 2-9.) If the detected paper width does not match the width for the selected page size, the
printer ignores the data which does not fit in the printable area of the paper. In case no change is
detected in paper size by the ASF PW sensor and ASF PL sensor, the CR PW sensor* is not
activated.
Note) *CR PW sensor: See Page 2-19.
Detecting Range
Paper Width (mm):D
(Length between right and left edge guides)
1
98=< =<108.6 / 123.4=< =<141.9
2
146.7=< =<151.9 / 161.6=< =<187.8
3
196.6=< =<232.1
4
231.8=< =<260.6
5
276=< =<283
6
293.6=< =<300.6
7
325.4=< =<332.6
8
349.6=< =<367.6
9
416.6=< =<423.1
10
429.1=< =<441
ASF_PL : Output from the PL (Paper Length) sensor.
Paper length is determined by three mechanical switches which detect the paper tray condition based
on the rear edge guide position and paper tray extension position. Each paper size range is detected
by the paper tray condition based on the combination of on/off status of the switches, as shown in
Table 2-10. The paper size is determined and memorized by combining the paper width and paper
length detected by the ASF PW sensor and the PL sensor.
Paper tray condition Corresponding sensor combination
Length Range Rear edge
guide
Paper tray
extension
Switch 1 Switch 2 Switch 3
Up to 158 mm 0 to 22 mm In On On Off
Up to 232 mm Up to 96 mm In On Off Off
Up to 260 mm Up to 125 mm In Off On Off
Up to 283 mm Up to 147 mm In Off Off Off
Up to 302 mm Up to 167 mm In Off On Off
Up to 623 mm Down
On On On
Table 2-9. Paper Width Range
Table 2-10. Paper Length Detecting Range
