Overspeed switch EGSH 41 ensures safely limited speed in the mill stand
- Safeguards personnel carrying out necessary work in the danger zone
- Switching points set without intervening in the PLC programming
- Safety certified encoder simplifies risk assessment
- Complete solution including safety mechanical parts and installation service
In addition to sensing speeds for motor control and protection it is also necessary to implement the safety function SLS (Safely-Limited Speed) for the main drive and for each coiler. The purpose behind this measure is to safeguard personnel in the danger zone as they carry out necessary inspection and maintenance work on machinery. The conceptual solution designed to implement SLS should also take into consideration reliable mechanical assembly.
The first step was to document the requirements and the installation conditions at the customer’s site before drawing up an overarching concept for the different points of installation. System solutions consisting of safety-certified, hollow-shaft type overspeed switches EGSH 41 (SIL 2 / PL d) as well as attachments calculated for safety and guaranteed fault exclusion are at the core of our customized solutions. An additional encoder with incremental output for motor control and a speed switching output for motor protection were integrated in the system solution as required. Hübner specialists installed all of the system components and carried out control measurements to verify the accuracy of the installed equipment and documented the results.