Weidmüller
Prepared for failures
Weidmüller relies on in-house developments to monitor its own ventilation systems for electroplating: The performance parameters are analyzed by the 'u-sense vibration' and 'energy direkt' sensors and with the 'Industrial AutoML' AI software.
The ventilation system at the Weidmüller electroplating plant in Detmold. The 'u-sense vibration' sensor was retrofitted to the fan motor and transmits the vibration data directly to the IIoT. The 'u-sense energy' sensor records the energy data of the fan system.
© WeidmüllerDigitalization makes production systems transparent: hidden potential is just as easily identified as emerging malfunctions at the earliest stage. Efficiency and plant availability can thus be increased to a degree that seemed unattainable just a few years ago. At the same time, the amount of data collected is constantly increasing.
In modern systems, only a fraction of this data has been specifically evaluated to date. Older systems are usually not digitized and data cannot even be recorded in some cases. However, with the right measures, existing systems can also be retrofitted economically, as the example of electric motors shows. These are regularly checked and maintained in order to prevent unplanned system downtimes - often purely manually, sometimes also via condition monitoring at control level. With u-sense, Weidmüller now offers a retrofit-capable solution for integrating motor monitoring directly into the IIoT in the shortest possible time. In addition, the data from the old systems can be integrated into the development of machine learning models (ML models).
Rotating devices such as motors, pumps and gearboxes can be found in millions of production plants. Depending on the load, they wear out at different rates. If costly failures are to be avoided, the devices must be carefully monitored - which also incurs costs. This applies in particular to manual inspections. It would be more efficient to integrate the data into an analysis tool.
Weidmüller relies on its own machine learning tool AutoML and the retrofit-capable u-sense solution for the ventilation system of its electroplating plant. Smart fan monitoring and data analysis with the Industrial AutoML tool ensure clean air in electroplating processes. Several fans are located on the roof of the electroplating plant for this purpose. Previously, the data and status of the fans were not recorded digitally. For maintenance and inspection, you had to literally climb onto the roof of the electroplating plant. In order to integrate the fans into the digital process, they were retrofitted with the universal u-sense energy drives current sensor and the u-sense vibration sensor. Both devices contain sensors and are suitable for installation close to the machine thanks to their robust housing and industrial-grade connection and communication technology.
Acquisition of all relevant electricity data
The u-sense energy drives are installed in the supply line and record all relevant electrical states of the motor. Industry-standard sensors are used to record the current and voltage curve with an accuracy of 3% at a sampling rate of 1 kHz. Additional sensors can be integrated as required via digital and analog inputs. A control module processes the recorded states and digitizes them so that both directly measured and calculated electrical variables are digitized. This means that not only measured values for voltage and currents of all phases are available, but also, for example, active and reactive power, switching cycles or operating hours. The recorded current values of the fan flow into the Industrial AutoML software as training data.
Vibrations also reveal a lot about the condition of a drive, which is why the u-sense vibration smart sensor was installed. Transmission takes place via Bluetooth Low Energy (BLE) 5.0, with a replaceable AA battery serving as the power supply. As the transmission is via BLE and therefore energy-saving, a service life of up to two years is possible.
The exhaust air blowers for electroplating in particular have many wearing parts, such as the motors or the drive belts that ultimately drive the impeller. The blower draws the air out of the electroplating process via a special filter system, thus ensuring a regular exchange of air. The filter technology used here meets the latest environmental criteria. The exhaust air blower, in turn, is connected to the building with a sleeve, which must guarantee appropriate tightness.
From reactive to predictive maintenance
A closer look at the ventilation systems revealed three key monitoring points: the drive belt, the impeller and the sleeve. Previously, these components were monitored manually or visually. By integrating the data into the Industrial AutoML software, service calls can now be planned in a targeted manner or only take place when required. This is accompanied by a shift from reactive to predictive maintenance.
But how can the data be analyzed? How do you create a machine learning model to analyze the extraction fans? The methods and tools of machine learning (ML) not only enable digital access to the data of the ventilation system, but also make it possible to identify relevant correlations.
Weidmüller wants to enable machine builders and operators to create ML models independently and thus convert the collected data into added value. To this end, the company has simplified the application of machine learning to such an extent that domain experts can use their knowledge of the machine or production process to independently implement ML solutions - without expert knowledge in the field of data science. The software helps to translate and archive the application knowledge into a reliable machine learning application. The expert focuses on their knowledge of machine and process behavior and links this with the ML steps running in the background.
With the Industrial AutoML tool, an ML model could be built and operated in four simple main steps: Data import, data enrichment, automated model creation and model deployment.
Create ML models for the ventilation system
Figure 1: ModelBuilder with model results and sensor data. With the 'AutoML ModelBuilder', users create, validate and export their own machine learning models.
© WeidmüllerUsing the AutoML ModelBuilder, the first module of the software, the Weidmüller specialists were able to generate an ML model for anomaly detection and classification(Fig. 1). To do this, the data from the ventilation system was fed into the system as training data. The monitoring of the motor and drive was particularly interesting. The experts recognize the deviations from 'normal' behaviour directly in the clear display of the data, can detect them, label them and thus enrich them for modeling. Using the current data, for example, it was possible to trace the tearing of the drive belts due to wear. The evaluated data showed a significantly slower motor start-up, as two out of five belts were broken.
When looking at the current values, there was also a clear drop in the starting current. This is logical, as less power is transferred from the motor to the drive when the belt is broken. As a result, the load is lower and consequently the current is lower. The changes were also reflected in the data from the vibration sensor, which is attached directly to the motor. These areas are detected and the data is labeled as a deviation. Now the technical experts only have to define what the model should detect and which values are really necessary to automatically detect anomalies. This means that the expert knowledge flows directly into the creation of the model. The first step of the expert's work is complete. The software checks whether all the data required to create the models is available. The data set enriched in this way is the input variable for the subsequent automated generation of the ML models. As a result, several models based on different algorithms and value parameters are proposed. The aim is to automatically find the most promising pipelines and models in the gigantic optimization space of ML possibilities. In the end, the user selects the most suitable model for their application according to their preferred parameters.
The particular advantage of AutoML software is that the user only has to concentrate on their data. The rest, i.e. the entire part of a data scientist, is taken care of by the software.
Figure 2: ModelRuntime with signal curve (vibration data only). With the 'AutoML ModelRuntime', users can operate, configure and evaluate their own machine learning models.
© WeidmüllerOnce the right models have been selected, the next step is to execute them (deployment). This can be done directly on the machine 'on premise' or in the cloud. Users configure and run their own ML models in the AutoML ModelRuntime, i.e. the runtime environment(Fig. 2). The ModelRuntime is configured using the interfaces provided. The model results are also made available via defined interfaces and can thus be incorporated into the further operational process, for example to trigger messages about the respective motor or drive status. The expert is informed directly if his machine is not running smoothly.
The electroplating ventilation system shows that both retrofitting and the use of machine learning are worthwhile. Maintenance of the exhaust fans is now event-driven, downtimes and errors are reduced and maintenance work is optimized. In addition, the maximum service life of the wearing parts is utilized. All in all, this saves costs, capacities and, ultimately, nerves.
















