Sensor Circuits - Epson DFX-8500 Service Manual

DFX-8500

SENSOR CIRCUITS

Figure 2-18 shows the sensor circuits in block diagram form. The printer has the following sensors:
1. Front and rear paper end sensors (photo interrupter)
2. Top paper end sensor (photo interrupter detects the TOF position)
3. Paper jam sensor (magnetic transistor)
4. Tractor select sensor (micro mechanical switch)
5. Pull tractor sensor (micro mechanical switch)
6. Carriage encoder sensor (photo interrupter)
7. Platen gap encoder sensor (photo interrupter)
8. Platen gap home sensor (micro mechanical switch)
9. Ribbon jam sensor (photo interrupter)
10. Cover open sensor (micro mechanical switch)
11. Printhead temperature sensor (thermistor)
12. Head fan temperature sensor (thermistor)
13. Paper width sensor (photo reflector)
14. Carriage motor isolation resistance sensor (monitored by the analog port of the CPU)
15. PSB/PSE board power off sensor (signal interface)
16. Top cover sensor (Hall effect sensor)
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