12 •
750-491 [1 AI DMS]
Applicaton examples
WAGO-I/O-SYSTEM
750
I/O
Modules
2.1.1.8 Applicaton examples
A load cell was connected to the module in an experimental test bed.
The load cell was fed with the terminal's 5 V supply voltage (U
V
), while the
reference voltage (U
ref
) and the bridge voltage were captured with the U
ref
and
U
D
channels respectively.
Technical data for the load cell:
5 kg = 2 mV/V
The weight is calculated as follows: Weight = (U
D
/ 2 mV) / (U
ref
/ 1 V) * 5kg
2.1.1.9 Connection examples
The connected resistor measurement bridge can be supplied by the module via
the conneU
V
and -U
V
(see following illustration) or by an external
voltage supply.
+U
D
-U
D
-U
V
S
S
+U
V
+U
ref
-U
ref
If the resistor measurement bridge is supplied by an external voltage supply, a
common ground (earth) potential must be made by bridging the -U
V
connec-
tion of the module to the externally -U
V extern
(see illustration down).
+U
D
-U
D
-U
V
S
S
+U
V
+U
ref
-U
ref
-U
V extern
+U
V extern
Fig. 2.1.1-3: Connection of a Resistor Measurement Bridge with external Supply
g049105x
