The Beckhoff KL1408 is an 8-channel digital input Bus Terminal designed for efficient and reliable acquisition of binary signals in industrial automation systems. Supporting a nominal 24 V DC operating range, the KL1408 offers high input density in a compact form, making it ideal for applications where cabinet space is limited but numerous inputs must be monitored.

Each of the eight inputs is designed according to the EN 61131-2 type 1/3 standard, ensuring compatibility with a wide variety of industrial sensors, switches, and pushbuttons. This standard compliance guarantees reliable detection of digital states across multiple device types and ensures interoperability within diverse automation environments.

The input circuitry supports clear and reliable voltage thresholds, with a “0” signal defined between -3 and +5 V and a “1” signal defined between 11 and 30 V (EN 61131-2 type 3). These defined switching points ensure consistent recognition of signal states even in environments subject to electrical noise or voltage fluctuations.

A built-in 3 ms input filter provides additional noise suppression, eliminating spurious transitions caused by contact bounce or electromagnetic interference. This feature is particularly valuable in industrial settings where reliability is critical, helping to maintain accurate system operation under challenging conditions.

The KL1408 employs 1-wire connection technology, simplifying wiring and reducing installation effort. By combining multiple inputs into a single terminal with streamlined wiring, the module improves system organisation and saves valuable time during commissioning.

Powered via the K-bus, the KL1408 integrates seamlessly into Beckhoff’s modular Bus Terminal system. This modularity allows it to be combined effortlessly with digital, analog, and specialty terminals, creating flexible and scalable I/O solutions tailored to specific application requirements. With its compact width, the terminal supports high-density I/O configurations while minimising cabinet space requirements.

Diagnostics and monitoring can be performed using Beckhoff’s TwinCAT automation software, which provides real-time visibility into input states and simplifies commissioning and troubleshooting. Engineers can quickly identify input conditions, reducing downtime and improving system efficiency.

The KL1408 is well-suited to a wide range of applications, including machine building, packaging systems, building automation, and process control. It is particularly effective in scenarios where multiple digital signals—such as limit switches, pushbuttons, or proximity sensors—must be acquired in a reliable and compact format.

In summary, the Beckhoff KL1408 is a high-performance 8-channel digital input terminal designed for 24 V DC applications. With EN 61131-2 compliance, reliable voltage thresholds, integrated input filtering, and compact 1-wire connection technology, it provides a cost-effective and space-saving solution for digital signal acquisition in Bus Terminal-based automation systems.