Siemens Simatic S7-400 - Manual (Page 315)

Analog Modules
5-99
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
5.21 Analog Input Module SM 431; AI 16 13 Bit;
(6ES7431-0HH00-0AB0)
Characteristics
The analog input module SM 431; AI 13  16 Bit has the following features:
• 16 inputs for voltage/current measurement
• Unlimited measuring range selection
• 13-bit resolution
• Non-isolated between the analog section and bus
• The maximum permissible common mode voltage between the channels and
the reference potentials of the connected sensors and central ground point is 2
VDC/VAC