HomeIndustryProcessSolutionsPrecisely connecting signals

Precisely connecting signals in process control systems

Diverse product range for marshalling, converting and protecting field signals


Proper signal transmission is often an immense project, particularly in process plants: Several thousands of field signals need to be wired to the DCS (Distribution Control System). In doing so, the clear and simple connection of the wires, their shielding, the protection against lightning and surges, as well as the conversion of the signals must be implemented in a precise and efficient way.


In response to these requirements, Weidmüller has designed a variety of precisely tailored solutions for connecting signals in process control systems. The following graph shows the product range at a glance:

1)  Signal Conversion



Intrinsically safe circuits to limit energy are used in explosion risk zones. In these circuits, the intrinsically safe signal converters with their galvanic isolation and Exi approved surge arresters provide excellent protection for sensitive control electronics. Lightning strikes and overvoltages in the field on measurement and control cables can lead to explosions.


The ACT20M unites innovative technology with maximum functionality in an electronics housing that is only 6 mm wide. Up to two channels per module help to save space in the electrical cabinet. High galvanic isolation of 2.5 kV and an accuracy of up to 0.05 % strengthen the reliability and safety of the process.

2) Functional Safety


SIL Relay

About 20 % of the signals in process and energy technology are processed in safety-related applications, e.g. emergency shutdown systems. Their task is clearly defined: Immediate and automatic initiation of corrective measures – up to the shutdown of plants and plant components - in case of danger. Weidmüller’s SIL relay is particularly suitable for these tasks and applications. It has been certified by TÜV Nord in accordance with EN 61508 for the safety requirement level SIL 3.

3)  Surge Protection for Instrumentation and Control Systems



The VARITECTOR SPC is characterised by highest protective functions with compact dimensions. The arrestor of the modules can be removed or exchanged during running operation impedance-neutral – without interrupting the measuring circuit. Thus, the product is ideally suited for protecting instrumentation, control and automation circuits.

4) Marshalling and Interfaces



Today’s control systems are increasingly more complex with higher and higher demands for the monitoring and capturing of operational data. These demands result an increasingly large number of field measuring devices. These trends pose new challenges to engineers. On one hand, the additional signals for the automation need to be connected and processed. On the other hand, extra space in associated with increased costs. These demands are met with Weidmüller’s new marshalling and distribution terminals. The PRV, with its PUSH IN wire connection, is the most compact marshalling terminal worldwide.

DCS Interface Units

The IOTAs (Input Output Terminal Assemblies) are designed using Weidmüller PCB connectors and terminals. This design allows the user the flexibility to go directly to the field cabling wire to wire or by a pre-assembled cable in combination with the Weidmüller FTAs. In comparison to the traditional wire to wire cabling the new Weidmüller FTAs and pre-cabling solution offer a highly efficient method of wiring between I/O modules and the field.