Overview
The 6ES7422-1HH00-0AA0 is a Siemens SM 422 digital output module for the SIMATIC S7-400 system, providing 16 relay outputs rated at 5 A per channel across a 5..230 V AC or 1..60 V DC range. The module draws 4.5 W from the backplane, occupies a 25 mm slot width, and is classified as Size 5 per NEMA. RoHS compliance dates from 01-03-08.
Function & operation
Each of the 16 relay outputs switches up to 5 A continuous at 230 V AC (resistive) or 60 V DC. The relay contacts are rated for 100 000 electrical cycles under AC-15 or DC-13 loads, and 3 000 000 mechanical cycles — a figure that governs maintenance intervals in high-duty applications. Each channel has a per-channel status LED for quick fault isolation on the cabinet door. Digital input control is possible, allowing the module to be read back for diagnostics, though no onboard diagnostics block is implemented.
Applications
This SM 422 relay output module is used in SIMATIC S7-400 racks to switch AC or DC loads such as contactors, solenoid valves, motor starters, and indicator lamps in industrial machine control, conveyor systems, and process skids. The 16 isolated channels suit applications requiring galvanic separation between the PLC backplane and field devices.