Locks play an essential role in shipping – without them, rivers and canals would not be traversable. At the same time, however, they also pose a risk as bottlenecks, and technical interferences on the huge lock gates can rapidly lead to congestion problems. Our case study shows how we used a position switch retrofit to eliminate problems when monitoring the gate position – with no complex changes whatsoever to the system control.
Moving a great deal of weight very slowly
Opening and closing lock gates requires both a large amount of power and maximum precision. The extremely heavy gates, which are usually between ten and twenty meters wide, are moved at a very slow speed, especially shortly before they reach their end position. If the position and speed monitoring are not completely reliable throughout this process, unwanted operational interferences may occur – and in the worst-case scenario, the locks may even be damaged.
A 1:1 replacement solution by Hübner Giessen
The Ems-North Sea Waterways and Shipping Office contacted us regarding a problem with the Herbrum lock on the Dortmund–Ems Canal, where a mechanical cam limit switch was constantly causing problems while closing the lock gates. The office was looking for a replacement solution that could be integrated into the PLC control system without any programming requirements. The solution also needed to provide the same safety and performance levels as the existing system and, of course, offer maximum precision. Our experts opted to use an encoder system with safety certification up to SIL 2 as a seamless replacement for the old mechanical cam limit switch. You can find out how the new solution was developed and installed and what other advantages it offers the lock operators in our case study: “Locks: Exchanging mechanical cam switches against electronic position switches results in trouble-free monitoring of the lock gate”.