A solder pot as part of the soldering module

Cost-effective automation of soldering systems with multifunctional safety relays In machine building, modular safety concepts are implemented with multi-functional PSR-MXF safety relays

Ersa GmbH places a very high value on safety technology. The company has modularized the safety concepts of its selective soldering systems so it can react flexibly to customer requirements. PSR-MXF multifunctional safety relays can be used in both simple machines and modular safety concepts.

Ersa soldering system under construction

Ersa GmbH – a soldering specialist

Ersa GmbH, based in Wertheim, Germany, is Europe’s largest manufacturer in the field of soldering technology.

The international supplier of selective and wave soldering systems provides services and solution packages for optimizing its customers’ production processes.

Multi-functional safety relays are used in this selective soldering system

The selective soldering process

The selective soldering process is often the only conceivable concept when components that are wired on both sides need to be soldered and a wave soldering process with the classic wave on the second side of the module is no longer possible.

Compared to the classic wave soldering system, the selective soldering system usually requires considerably less space. Its minimal configuration consists of a programmable high-precision fluxer for applying the flux, a preheater module, and the actual soldering module.

Depending on customer requirements, the function of the selective soldering system can be extended to include further units, each comprised of a preheater and a soldering module. Such a concept requires compact devices that are easy to handle and can be flexibly adapted to the respective conditions.

Installation of PSR-MXF multi-functional safety relays in a selective soldering system control cabinet

Use of multi-functional safety relays in selective soldering systems

Based on the requirements described above, Ersa uses PSR-MXF multifunctional safety relays from Phoenix Contact in its Versa-Flow series. This is because the narrow safety component, which measures just 22.5 millimeters, can process two local and one higher-level sensor circuit up to Performance Level PL e or Safety Integrity Level SIL CL 3. The small size is possible thanks to the use of the three-level MEmax housing from the Phoenix Contact product portfolio with a total of 24 contact points, among other things.

The tool-free Push-in connection technology was also another important criterion that convinced Edgar Diener, who is responsible for the electrical design of selective soldering systems, to opt for PSR-MXF safety relays.

From now on, I only really want to use components with direct connection technology, which permits quick and easy wiring.

Edgar Diener - Ersa GmbH, Electrical designer
Edgar Diener, electrical designer at Ersa GmbH
Topology with multi-functional MxF safety relays for various safety functions

Multi-functional safety relays easily implement modular machine concepts

As the example of a selective soldering system demonstrates, the multi-functional safety relay’s patented concept allows even modular machine concepts to be implemented with ease. Thanks to the functionality integrated into the safety relay, the effort involved in verifying and validating the safety solution is reduced considerably compared to alternative concepts.

Every additional module of the soldering system that contains its own control cabinet fits seamlessly into the existing concept, because the higher-level emergency stop signal from the fluxer module is processed by all downstream parts of the circuit. During the safety assessment, the participants also specified that the door locking mechanisms of the individual function units must always affect the upstream and downstream modules.

In the future, we’ll be using the basic version, which accounts for a considerable proportion of the total series volume, with one instead of three safety relays.

Edgar Diener - Ersa GmbH, Electrical designer
Edgar Diener, electrical designer at Ersa GmbH
Figure shows an overview of different safety relays

Explore our comprehensive product portfolio of safety relays Large selection of safety and coupling relays for reliably monitoring functional safety in your machine

Would you like to integrate safety relay modules in your machine or system? We offer you a comprehensive product portfolio of safety relays, whether it’s over-speed and zero-speed safety relays, extra narrow safety relays, or safe coupling relays. Call us or follow the link for detailed information around safety relays.