Siemens SIMATIC ET 200C Manual page 101

Voltage Sensors
Voltage sensors can be connected for the measured-value ranges
The settings of the switches in DIL switch block S4 determine whether mea-
surement is floating or non-floating (see Section 4.4.1).
Note
If a voltage sensor is used for floating measurement, the maximum
permissible common-mode voltage is U
overshot relative to M
The illustration below shows how voltage sensors are connected in a 2-wire
circuit for floating measurement:
Figure 4-21
ET 200C Distributed I/O Station
EWA 4NEB 812 6119-02b
2.5 V, 5 V, 10 V.
at any differential input.
ANA
+
U
CH0
–
+
U
CH1
–
.
CH2
Shield
CH3
M
ANA
Connection to ET 200C; AI 4
Circuit for Floating Measurement
Mechanical and Electrical Installation
1 V and must not be
CM
+
–
+
–
+
–
+
–
12 Bit of Voltage Sensors in 2-Wire
1.25 V,
4-33