Siemens 6ES7421-1BL01-0AA0 Digital Input Module

Description

The Siemens 6ES7421-1BL01-0AA0 Digital Input Module, also designated as SM 421, is a specialized industrial automation component designed for use with the S7-400 series PLC system. It features optical isolation and offers reliable digital signal input expansion for automated control setups. Key technical specifications include 32 digital input channels, a 24V DC operating voltage, and a maximum power loss of 6W. The module draws input current from the backplane bus at 5V DC, with a maximum of 20mA, and maintains full 32-channel operation at temperatures up to 60 degrees Celsius.

Equipped with versatile input compatibility, it supports both PNP (sink input) and NPN (source input) type sensors, enabling adaptation to diverse industrial signal sources. Its robust construction ensures stable performance in harsh environments with high temperatures and humidity. The modular design simplifies installation, configuration, and system expansion based on operational needs. Integrated diagnostic features enhance maintainability: front-panel indicators for status, power voltage, and faults provide real-time visibility, while support for channel or module-level open-circuit and short-circuit diagnostics, plus value status monitoring, enables quick issue identification and resolution. The module carries CCC product certification and is engineered for seamless integration with other S7-400 series components.