Input Wiring Precautions - Panasonic FP0R User Manual

5.5.1.2 Input wiring precautions

When using an LED-equipped Reed switch
When using a two-wire type sensor
FP0R User's Manual
When an LED is connected in series to an input contact such as an
LED-equipped Reed switch, make sure that the ON voltage applied to the
PLC input terminal is greater than 21.6V DC. In particular, take care when
connecting a number of switches in series.
LED-equipped Reed switch
FP0R
Q LED
W Contact
E 21.6V
R Input terminal
If the input of the 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 below.
Two-wire type sensor
FP0R
Q Internal circuit
W Bleeder resistor
E Input terminal
Installation and wiring
75