Siemens SIMATIC S7-400 Reference Manual page 254

Analog modules
5.21 Analog input module SM 431; AI 8 x 14 Bit (6ES7431-1KF20-0AB0)
● Resolution 14 bits
● Supply voltage: 24 V DC only required for connection of 2-wire transducers
● Analog section isolated from the CPU
● Maximum permitted common mode voltage between the channels or between the reference
potentials of the connected sensors and M
Circuit diagram for SM 431; AI 8 x 14 bit
CH0
CH1
MANA
CH6
CH7
Figure 5-27
254
Measuring
range
module 0
Measuring
range
module 3
+ 5V
L+
+ 15V
M
MANA
- 15V
Circuit diagram for SM 431; AI 8 x 14 bit
8 V AC
ANA
D
ENABLE
+5V
0V
0V
Reference Manual, Ausgabe 11/2016, A5E00850736-08
Bus S7-400
Bus S7-400
Bus S7-400
S7-400 Automation System Module Data