Siemens 6ES7231-4HF50-0XB0 SIMATIC S7-1200 SM 1231 8AI 14-Bit Analog Input Module

The Siemens 6ES7231-4HF50-0XB0 is a SIMATIC S7-1200 SM 1231 analog input module with 8 channels of 14-bit differential voltage or current inputs (plus/minus 10 V, 5 V, 2.5 V, or 0/4-20 mA). It plugs onto the S7-1200 backplane bus and converts all 8 channels in a maximum cycle time of 1.25 ms. Input resistance is at least 1 MOhm on the voltage ranges.

Technical Specifications

Certifications & Standards

• CE
• UL
• cULus
• RCM
• KC

Selection Notes

This SM 1231 variant offers 8 configurable channels, useful when a single module needs to cover mixed voltage and current transducers on one backplane slot. Each channel independently selects between +/-10 V, +/-5 V, +/-2.5 V, or 4-20 mA/0-20 mA, so sensor types can be mixed without adding a second module. The 1.25 ms full-scan cycle time across all 8 channels, with 400 Hz noise rejection, keeps this module fast enough for process loops that poll analog values every control cycle.

Applications

Typical uses include reading 4-20 mA process transmitters for pressure, level, and flow, plus/minus 10 V analog sensors, and mixed sensor types on machine and process skids controlled by an S7-1200 CPU.