Siemens 6ES7 321-1BH01-0AA0 SM321 Digital Input Module ⚙️ 16-DI 24VDC S7-300 Used

Used, reliable Siemens SIMATIC S7-300 Digital Input Module SM 321 (6ES7 321-1BH01-0AA0). This module provides 16 optically isolated digital inputs compatible with standard 24V DC signals, making it essential for reading field devices like buttons, switches, and sensors in industrial control systems.

Technical details in bullet points:

Brand: Siemens

Model: SM 321 (Digital Input Module)

Part No.: 6ES7 321-1BH01-0AA0

Series Compatibility: SIMATIC S7-300

Number of Inputs: 16 Digital Inputs (DI)

Input Voltage: 24 VDC

Isolation: Optically Isolated

Input Delay: 7.5 ms (Standard response time)

Module Format: Standard (Requires 20-pin front connector, usually sold separately).

Condition: Used, Tested

Any included accessories: Module unit only (Front connector, cables, and sensor leads are NOT included).

Condition and notes: This Digital Input Module is USED and was pulled from a working control system. The unit has been tested and confirmed to power on and register input signals correctly. Expect minor cosmetic wear, light surface scratches, or dust accumulation typical of a used industrial component. This model is a core piece for S7-300 maintenance.