Epson DFX-8500 Service Manual page 77

DFX-8500
Each sensor is described below.
1. Front and rear paper end sensors


Detection form:


Output form:


Logical states:
2. Top paper end sensor (detects the TOF position)


Detection form:


Output form:


Logical states:
3. Paper jam sensor


Detection form:


Output form:


Logical states:


Note:
4. Tractor select sensor


Detection form:


Logical states:
5. Pull tractor sensor


Detection form:


Logical states:
6. Carriage encoder sensor


Detection form:


Transaction:
7. Platen gap encoder sensor


Detection form:


Output form:


PG response:


Available range:
2-24
Photo interrupter
Open collector (pulled up to 10 kΩ resistor)
Paper present: LOW
Paper out: HIGH
Photo reflector
Open collector
Paper present: LOW
Paper out: HIGH
Magnetic transistor
Rectangle wave (1 channel, TTL level)
Paper feed: Signal level changes continuously.
Paper jam: Signal level remains the same.
The magnetic transistor is attached to the tension roller on the paper
tension unit.
Micro mechanical switch
Front tractor: LOW (closed)
Rear tractor: HIGH (open)
Micro mechanical switch
Pull tractor installed: LOW (closed)
Pull tractor not installed: HIGH (open)
Photo reflector
Rectangle wave, A and B phases.
Photo interrupter
Rectangle wave, 2 channel
T = 0.015 mm / pulse
0 < T < 0.7 mm