Epson SRC520 Manual page 61

Typical Input Circuit Application 2 : PNP type (the European standard)
470 Ω
2.2 kΩ
(ditto)
(ditto)
(ditto)
(ditto)
(ditto)
～
～
(Omit)
Function 6.1 Input Circuit (D-I/O Connector)
1 Input No.0 to 3 common
2 Input No.0
3 Input No.1
4 Input No.2
5 Input No.3
26 Input No.4 to 7 common
27 Input No.4
28 Input No.5
～
～
GND +DC
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