Thinking outside of the Box - LAPP develops predictive maintenance device for Ethernet cables
Predictive maintenance is one of the most important and most anticipated benefits of digitalisation in factories. Instead of replacing parts only when they have already broken down (reactive maintenance) or replacing them while they are still functional (preventive maintenance) - predictive maintenance is based on the analysis of actual data recorded on the production line. Obviously the question of how to implement predictive maintenance also concerns connection networks. Cables have an extended life span compared to other industrial components, however failure cannot be completely ruled out, especially in demanding applications. A faulty cable can paralyse the entire production line and cause high profit loss. "That's why we want to offer a solution that will ring the alarm before a cable fails," says Guido Ege, Head of Product Development and Management at LAPP.
Focus on Ethernet
We developed our solution based on Ethernet cables laid in drag chains. When placed in such a demanding application, data cables are more prone to failure because of their complex structure and high-frequency characteristics. With Ethernet cables, a damaged outer sheath leads to increased EMC interference; broken strands can also cause the data rate to drop and can even result in communication to stop completely.
LAPP’s aim is to predict the remaining lifetime of a data cable and plan replacement in a timely and cost effective way, with minimum disruption to the running of the machine.
The solution… in a box
At LAPP we know timing is everything, which is why we have developed a solution without so-called “sacrificial wires” which would require additional installation work. Instead, we have worked on a solution based on a protocol and a special algorithm that allows the use of standard Ethernet cables and connectors such as RJ45 or M12.
The measurement takes place in a Predictive Monitoring Box (PMBX). The PMBX has two Ethernet ports and is simply inserted at the beginning of the Ethernet cable that needs to be monitored. The data packets are transmitted transparently from one Ethernet port to the other, almost without delay. For a connected PLC, the PMBX is not visible, it has no influence on the data transmission. It is therefore also suitable for existing systems without having to make any changes to the PLC software.
LAPP Predictive Indicator
This kind of predictive maintenance uses a deep learning approach. The Box sits in between the robotic applications and the PLC, tracking data flow from one end to the other and monitoring any fluctuations in performance. Based on these, the LAPP Predictive Indicator is calculated which gives useful information about the service life expectancy of the cable and when it is time to replace it. The solution was tested on LAPP drag chain cables: millions of measured values were collected in our in-house test centre and then analysed using mathematical algorithms. The more data available, the more accurate the prediction. At a later stage, customers will be able to access this data directly from their PC or from the cloud – depending on their requirements.
The new predictive maintenance system was first presented at LAPP’s FutureLab during Hannover Messe 2019. "We are in discussions with a number of interested parties and pilot customers who want to integrate our solution into their specific applications," says Guido Ege, "the next step is to develop a suitable business model.”