Safe automation
When designing safe automation, we use the Siemens Safety Evaluation Tool software, tested by TÜV, or SISTEMA developed by the German Institute for Occupational Safety IFA. It allows modeling the structure of the designed safety parts of control systems, working with known terms like PLr, MTTFd, PFHD, etc. The output is the verification of the relationship PL≥PLr (calculated level is higher or equal to the required level).
We address the safety concept of the designed equipment already during the initial project processing; PLCs are much more often designed in safety versions, i.e., Allen-Bradley GuardPLC from Rockwell Automation or Simatic Safety Integrated from Siemens.
The aspect of safety in the design of machines and equipment is crucial. We cooperate with mechanical designers and technologists. We always keep in mind the risk graph according to ČSN EN ISO 13849-1, which works with the following input parameters:
- severity of injury – S
- frequency and/or duration of exposure – F
- possibility of avoiding the hazard or limiting harm – P
Sample Case Studies
Warehouse Management and Cutting of Al Semi-finished Products for a Customer in Norway
A new device for handling, storing, and cutting as yet undivided semi-finished products using Allen Bradley technology is installed before the existing production process. The equipment is designed in the SIL3 / category 4 safety category according to EN 954-1. GuardLogix replaces the current ControlLogix, newly designed are ethernet Point I/O modules, PanelView Plus 700 operator interfaces, frequency converters of the 70 series and the new 755 series with Safe Torque Off extension.
Reconstruction of the Control System for the Firing Plant of a Thermal Dryer for Flotation Concentrate and Coal Slurries with a Capacity of 24 MW
The existing Siemens Simatic S5-135F safety redundant control system is being modernized; the newly designed control system Simatic S7-317F uses safety digital modules SM326. Safety function blocks designed for gas and oil burners are used to control the ignition and main burner.
