Siemens Simatic M7-400 Reference Manual page 534

Interface Submodules
Isolated Measured Value Sensors
Potential differences can occur between the individual measured value sensors in
the case of isolated measured value sensors. These potential differences can
occur as the result of interference or the physical distribution of the measured value
sensors.
Note
Ensure that the V
value. Violation of the permissible value can result in wrong measured values.
Figure 13-13 shows the connection of isolated measured value sensors.
Isolated measured
value sensors
Figure 13-13 Connection of Isolated Measured Value Sensors
13-38
(common mode voltage) does not exceed the permissible
CM
+
V
E0
-
+
V
CM0
-
+
V
E1
-
+
V
CM1
-
M
SENSOR
S7-400, M7-400 Programmable Controllers Module Specifications
MV
0+
M
0-
MV
1+
M
1-
Ground bus
A5E00069467-07