NAVTELECOM SMART S-2425 Operation Manual page 18

Profiles "Discrete NC+" and "Discrete NO+" allow to work with sensors, which, when turned on or off, close the input
to "+" supply voltage.
+U
+U
+U
2–10
кОм
Figure 25. Connection of normally closed (NC-) sensors to UIN1
Figure 26. Connection of normally open (NO+) sensors
Figure 27. Connection of normally closed (NC+) sensors
UIN
R
1
C
1
VDD
R
pu
UIN
R
1
C
1
VDD
R
pu
UIN
R
1
C
1
CPU_adc
R
2
CPU_pull-up
CPU_adc
R
2
CPU_pull-up
CPU_adc
R
2