Epson DLQ-3000 Service Manual page 44

Operating Principles
Table 2-14. Paper Feed Sensor Specifications PEW Detector and Paper
Detection Element
Detection Method
output
Power Supply Voltage
Collector Explosion Proof
Signal Mode
2-12
Loading Sensor (Common Spec.)
Photo-reflector
Photoelectric Transfer (Before the paper end is detected, the
detector voltage is sampled and the voltage is compared with
the voltage measured after the paper-end detection to judge
whether or not paper is loaded.
Open collector
5VDC k 5~o
30 V or less
Paper is loaded:
Before Paper-end Sampled Voltage >/= After Paper-end
Detection Voltage
Paper is not loaded:
Before Paper-end Sampled Voltage > After Paper-end
Detection Voltage
I
1
I
r
I
Paper
Paper Feed Sensor
Figure 2-7.
I
PEW Sensor
r
,
, t
I
Loading
I
-
Sensor