Siemens 6ES5 421-8MAQ2 Digital Input Module 8x24VDC

Siemens 6ES5 421-8MAQ2 is an eight-channel digital input module designed for SIMATIC S5 PLC systems, delivering eight 24 V DC input points that let the controller interpret the on/off state of connected devices and signals in a wide range of industrial environments, from manufacturing lines to packaging and material handling zones. In practice, the module is used to capture 24 V DC sensor and switch signals—such as pushbuttons, limit switches, and proximity devices—and feed discrete data to the S5 CPU so the software can perform digital logic, sequencing, interlocks, and basic automation tasks that coordinate equipment, conveyors, and process flows. As part of the 6ES5 421 input module family, the 8MAQ2 is designed to install in compatible SIMATIC S5 racks and to integrate with standard Siemens backplane wiring conventions, enabling scalable expansion of legacy automation installations without requiring a new controller, while maintaining continuity with familiar programming practices and addressing schemes.