Epson C117001-N - DFX 5000+ B/W Dot-matrix Printer Service Manual page 63

Operating Principles
Paper thickness sensor
8.
Platen gap home position sensor
9.
10. +35 VDC voltage drop sensor (signal interface)
When the +35 VDC line voltages drop, the C117 power supply board assembly sends a HIGH
11. Head temperature sensor (uses a thermistor)
12. Fan temperature sensor (uses a thermistor)
13. Paper width sensor
To provide information about the carnage motor life, the analog port (ANO) of the CPU checks
the isolation resistance every time the printer is turned on. If the isolation resistance is less than
Operation.)
2-24
Photo interrupter
Rectangle wave (2 channels, TTL level)
CR filter circuit (10 KQ and 390 pF)
0.015 mm/pulse
O to 0.7 mm
Micro mechanical switch
Resistance for latch up prevention (10 KCt)
Pulled up to 390 ~ resistance
Pulled up to 3.32 KCl resistance
CR filter circuit (1 KKt and 0.1 pF)
Pulled up to 3.32 Kf2 resistance
CR filter circuit (1 K$i2 and 0.1 p.F)
Photo reflector
Emitter follower
CR filter circuit (10 KLt and 0.01 pF)
No paper present: Standard voltage level.
Paper present: The voltage level is double the standard voltage level.
resistance sensor (monitored by port ANO of the CPU)
Rev. A