Siemens 6ES5421-8MA11 Digital Input Module for SIMATIC S5

The 6ES5421-8MA11 captures discrete field signals for SIMATIC S5 controllers. This module reads status from push buttons, limit switches, and selector switches. You can rely on it for machine monitoring and interlock applications.

Key Technical Parameters

The table below lists all essential technical specifications for this digital input module.

Physical Characteristics and Installation

This digital input module weighs approximately 0.52 kg for standard rack mounting. Its dimensions measure 250 mm x 25 mm x 210 mm for S5 single-width slots. First, slide the 6ES5421-8MA11 into a free I/O rack position. Then, connect your sensors to the screw terminals. Finally, secure the module using the top and bottom locking screws. LED indicators on the front show the real-time status of every input channel.

Input Specifications and Signal Detection

The 6ES5421-8MA11 provides 16 digital input channels for versatile field connectivity. Each channel accepts 24V DC nominal signals from industrial sensors. The module draws only 8 mA per channel for reliable detection. Input impedance measures 3 kΩ for proper signal loading. Optocouplers isolate every input from the internal backplane bus. Consequently, this design protects the controller from electrical noise.

Response Time and Power Requirements

This input module delivers a 3 ms response time for standard machine applications. Each channel responds within milliseconds to any signal change. The 6ES5421-8MA11 draws its operating power from the 5V DC backplane supply. The total current consumption reaches 200 mA under full load. You do not need any external power source for the logic circuits. The screw terminal block provides reliable field wiring connections.