Automatic process control systems not only increase the safety and stability of the soldering process, but above all reduce the risk of potential soldering errors. This essentially reduces the costs of manufacturing electronic products. Many basic components of a soldering system have been monitored for some time. These include, for example, the temperatures in the preheating area, the filling levels of the flux reservoir and soldering pot, or the transport of assemblies through the system using appropriate sensors.
The stable height of the solder wave is also relevant to the process. Poor penetration or insufficient wetting can be the result of an irregular wave height, which is why they have long been automatically monitored and controlled in selective soldering processes.
There are also methods for wave soldering processes, but they are all associated with limitations: The wave height is not measured across the entire width, production has to be interrupted or it is not possible to draw conclusions about individual production.
SEHO has developed the automatic wave height measurement with a focus on precisely this aspect.
The system is based on contact measurement across the entire wave width, which ensures reliable results and processes, for both laminar and turbulent solder waves and it does not affect the cycle time of the wave soldering system.
To determine the ideal state of the wave height, a reference measurement is first carried out. In production mode, the height of the wave is then measured automatically in a programmable time grid. Based on these measurement results and a mathematical model, the wave height is automatically regulated within adjustable tolerances. All measurement results and readjusted parameters are of course documented for complete traceability.
The advantages are obvious: process deviations are detected at an early stage and the cause can be quickly analyzed and rectified. This ensures high product quality and production costs are sustainably reduced by avoiding rework or scrap.
