Siemens S5-135U/155U System Manual page 472

Analog Input/Output Modules
The channels have the following designations on the module:
Channel 0:
Channel 1:
Channel 7:
Channels are arranged in groups of four, for which you can set separate
measuring ranges:
Channel group I:
Channel group II: Channels 4 to 7
The following figure shows the connection of sensors to the module.
You must observe the following condition:
U
E
(i.e. the sum of the set voltage range and common-mode voltage must be less
than 12 V; current measuring ranges correspond to a voltage of 2.5 V).
+
U
E2
–
+
–
U
CM2
U
E1
U
CM1
U E1/2: Input Voltage
U CM1/2: Common-Mode Voltage
U ISO: Potential Difference
: Equipotential; this potential is established by the sensor reference potential
(external reference potential)
Figure 9-31 Connecting Sensors to the 466 Analog Input Module (Differential Measurement)
9-90
M0 +
M0 –
M1 +
M1 –
: :
M7 +
M7 –
Channels 0 to 3
+ U < 12 V
CM
Analog Input Module
M+
M–
MUX
M+
+
M–
–
+
0 V
ext
–
U
ISO
0 V Bus
System Manual
C79000-G8576-C199-06