Siemens SM322 Digital Output Module for SIMATIC S7-300

The Siemens SM322 (SM322) is a digital output signal module designed for use within the SIMATIC S7-300 automation system and ET 200M distributed peripheral stations. Installed on the S7-300 backplane bus, this signal module converts the internal logic states of the central processing unit into industrial control signals suitable for driving field actuators. It commonly interfaces with external devices such as contactors, solenoid valves, motor starters, indicator lights, and auxiliary relays across manufacturing and process control environments. Engineered for modular PLC configurations, the SM322 provides dependable channel-to-backplane electrical isolation and connects seamlessly into standard S7-300 subracks using standard front connectors. It integrates into engineering environments like STEP 7 and TIA Portal, allowing straightforward hardware configuration and comprehensive channel diagnostics. The rugged enclosure supports space-saving installation in centralized control cabinets and distributed remote I/O enclosures, making it an essential replacement component for plant maintenance, factory retrofits, and assembly automation systems.