Siemens 6ES7231-4HD32-0XB0 SIMATIC S7-1200 SM 1231 4AI Analog Input PLC I/O Module

The Siemens 6ES7231-4HD32-0XB0 is a SIMATIC S7-1200 SM 1231 analog input module with 4 differential channels, each configurable for ±10V, ±5V, ±2.5V, or 0-20mA/4-20mA input and 12-bit-plus-sign (13-bit) resolution. It draws 24V DC and adds diagnostic alarms for wire-break and supply-voltage faults on an IP20-rated housing, and it plugs into any S7-1200 CPU base or SM expansion slot without extra wiring accessories.

Technical Specifications

Certifications & Standards

• CE
• CSA
• UL
• cULus
• FM
• RCM
• KC
• Marine

Selection Notes

Each of the 4 channels independently accepts voltage (±10V/±5V/±2.5V) or current (0-20mA/4-20mA) inputs, so this module covers mixed sensor types on one card instead of needing separate voltage-only and current-only modules. The 625 µs max cycle time across all 4 channels and ±0.1% basic error limit at 25°C make it suitable for process signals that need fast, accurate scanning, such as pressure, flow, or temperature transmitters. Wire-break diagnostics flag an open 4-20mA loop at the module level rather than waiting for the PLC program to catch a stuck value.

Applications

Process instrumentation input on SIMATIC S7-1200 stations — pressure transmitters, flow meters, and 4-20mA loop-powered sensors in compact machine control panels.