Endress+Hauser NRF81 - Page 64

Commissioning Tankside Monitor NRF81
64 Endress+Hauser
9.2.5 Configuration of the digital inputs
D
E
F
C
B
A
1
1
1
1 3
2
2 4
1
HR
CDI
WP
on
SIM
2
2
3
3
4
4
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
POWER
A
1 2 3 4
A1-2 A3-4
i
C
1
2 3 4 5 6 7
C1-2 C3-4
A0026424
 31 Possible locations of the Digital I/O modules (examples); the order code defines the number and location
of digial input modules →  20.
There is a Digital Xx-x submenu for each digital I/O module of the device. "X" designates
the slot in the terminal compartment, "x-x" the terminals within this slot. The most
important parameters of this submenu are Operating mode and Contact type.
The "Operating mode" parameter
Setup → Advanced setup → Input/output → Digital Xx-x → Operating mode
DIO
2/4
+
_
2/4
1/3 1/3
A
DIO
B
A0029262
A "Operating mode" = "Input passive"
B "Operating mode" = "Input active"
Meaning of the options
• Input passive
The DIO module measures the voltage provided by an external source. Depending on the
status of the external switch, this voltage is 0 at the input (switch open) or exceeds a
certain limit voltage (switch closed). These two states represent the digital signal.
• Input active
The DIO module provides a voltage and uses it to detect whether the external switch is
open or closed.
The "Contact type" parameter
Setup → Advanced setup → Input/output → Digital Xx-x → Contact type