Case Studies

Control Panel Design for Hazardous Locations

Posted in Chemical, Manufacturing Automation and Intelligence, Oil and Gas Engineering, PLC Programming, Siemens PLC, Test & Measurement Automation


DMC worked with a client to create a turnkey panel and programming for controlling a piece of equipment that would be used in a hazardous environment.


DMC designed a control system for centrifuge for the client that would be used in a Class 1 Division 2 (C1D2) Enclosure with a purge system.

The NFPA Publication 70, NEC, and CEC defines Class II locations as those in which combustible dust may be found. The subcategory of divisions that the classes are further subdivided into define the likelihood of the hazardous material being present in a flammable concentration.

Division 2 is defined as follows:

“In which ignitable concentrations of hazards are handles, processed, or used, but which are normally in closed containers or closed systems from which they can only escape through accidental rupture or breakdown of such containers or systems.

We used a Factory Acceptance Test (FAT) because the hazardous environment was not present. This FAT tested functionality and verified that, if someone were to open the door, the purge would be lost and that we killed power to the entire panel. Overall, the test proves that we eliminated the risk.

Our engineers provided support in successfully completing this project the client had already started. With our expertise and programming experience, we successfully provided a solution that can operate in a C1D2 hazardous environment.

Read more about DMC’s manufacturing automation & intelligence services and contact us to get started on your next project.

Customer Benefits

  • Quality solution that can operate in a C1D2 hazardous environment
  • Robust programming
  • Software remained consistent
  • Updated hardware created for the certain environment
    • Enclosure specified with proper hazardous location rating
    • Added Purge System with feedback to PLC and hardwired connection to panel disconnect
  • Positive pressure differential inside of the panel