Panasonic FP0R Series, User Manual

Page: 60 / 348

5-8
5.3 Wiring of Input and Output
5.3.1 Input Wiring
Connection of photoelectric sensor and proximity sensor
Relay output type NPN open collector output type
Voltage output type
Two-wire output type
Precaution when using LED-equipped reed switch
When a LED is connected in series to an input
contact such as LED-equipped reed switch,
make sure that the voltage applied to the PLC
input terminal is greater than the ON voltage. In
particular, take care when connecting a number
of switches in series.
Precaution when using two-wire type sensor
If the input of PLC does not turn off because of
leakage current from the two-wire type sensor
"photoelectric sensor or proximity sensor", the
use of a bleeder resistor is recommended, as
shown on the left.
The formula is based on an input impedance of
9.1 k
Ω
.
The input impedance varies depending
on the input terminal number.