Siemens S5-135U/155U - Manual (Page 472)

9-90
System Manual
C79000-G8576-C199-06
The channels have the following designations on the module:
Channel 0: M0 +
M0 –
Channel 1: M1 +
M1 –
: :
Channel 7: M7 +
M7 –
Channels are arranged in groups of four, for which you can set separate
measuring ranges:
Channel group I: Channels 0 to 3
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
+ U
CM
< 12 V
(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).
M+
M–
M+
U
ISO
MUX
0 V Bus
+
–
+
–
U
E2
U
CM2
+
–
+
– U
CM1
M–
0 V
ext
U
E1
Analog Input Module
U E1/2: Input Voltage
U ISO: Potential Difference
: Equipotential; this potential is established by the sensor reference potential
(external reference potential)
U CM1/2: Common-Mode Voltage
Figure 9-31 Connecting Sensors to the 466 Analog Input Module (Differential Measurement)
Analog Input/Output Modules