Siemens 6ES7231-4HD32-0XB0 SIMATIC S7-1200 SM 1231 Analog Input Module 4AI 24V DC

4‑channel analog input module for SIMATIC S7‑1200 systems, accepting voltage (±10V, ±5V, ±2.5V) or current (0‑20 mA, 4‑20 mA) signals for precise measurement of sensors and transmitters in industrial automation applications.

The Siemens 6ES7231‑4HD32‑0XB0 is an SM 1231 analog input module for the SIMATIC S7‑1200 PLC family. It features 4 differential input channels, 13‑bit ADC resolution (12‑bit + sign), adjustable integration time for noise suppression, and diagnostic functions including supply voltage monitoring and wire‑break detection. The module clips directly onto the DIN rail next to S7‑1200 CPUs (except 1211C) and is configured via TIA Portal.

Applications

• Process monitoring (pressure, flow, level, temperature)

• Analog signal acquisition from voltage or current transmitters

• Industrial automation and production lines

• OEM machine building and equipment control

• Quality control and test systems

Key Features

• 4 configurable inputs: voltage (±10V, ±5V, ±2.5V) or current (0‑20 mA, 4‑20 mA)

• 12‑bit + sign resolution (13‑bit ADC), update time ≤625 µs for all channels

• Adjustable integration time for 50/60 Hz noise suppression

• Diagnostics: supply voltage monitoring, wire‑break detection for 4‑20 mA loops

• 24V DC power, 80 mA backplane current, 1.5 W power loss

• Dimensions (W × H × D): 45 × 100 × 75 mm, 0.161 kg weight

• IP20 protection, -20°C to +60°C operational temperature

• Certifications: CE, CSA, FM, Marine, RCM, UL

Technical Specifications

System Integration

• PLC Controllers: SIMATIC S7‑1200 (CPU 1212C, 1214C, 1215C, 1217C; not CPU 1211C)

• Configuration Software: TIA Portal (STEP 7 Basic or Professional)

• Mounting: DIN rail, side‑by‑side with CPU on the right

• Wiring: Front connector (screw or spring‑type, sold separately)

Related Products

• PLC Controller: Siemens 6ES7215‑1AG40‑0XB0 S7‑1200 CPU 1215C – system core

• Analog Output Module: Siemens 6ES7232‑4HD32‑0XB0 SM 1232 – output pairing

• Digital I/O Module: Siemens 6ES7221‑1BH32‑0XB0 SM 1221 – digital input expansion

• Front Connector: Siemens 6ES7292‑1AX30‑0XA0 – 20‑pin screw‑type connector

PLC ERA is an independent industrial automation distributor. Products are sourced from established supply channels and inspected before shipment. International shipping available.