CNC4PC C25S User Manual page 7

Wiring diagram to connect NPN proximity sensors with internal pull up resistor
Some NPN proximity sensors have an internal pull-up resistor (R1). It is necessary to
know its value in order to safely connect the sensor with the BOB. Follow this
recommendation:
Connecting NPN open collector proximity sensor with the C25
(R1+R2) Value (12V) (R1+R2) Value (24V)
Aprox. 10KΩ Aprox. 25KΩ
CALCULATING THE R1 VALUE
Note: Rx is the unknown resistor value.
R = V .(R/V) - R (1)
X EX
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