Air Liquide GmbH in Stade, Germany
Time and space saved due to the process interface concept
Gases such as nitrogen, oxygen, argon, carbon dioxide, hydrogen and carbon monoxide are produced at the facility in Stade.
The application
Since the production capacities had to be increased considerably, planning a quick and flexible system enhancement was an important task for engineers and technicians. The extension had to be done within a short span of time. Production should have been interrupted only for 40 days.
700 new signals were integrated in a network of control systems (PLS) and safety-related controllers with 1200 analog and digital input/output signals. Approximately 30% of the signals were safety-related and classified as per SIL 2 in accordance with the IEC 61508 standard.
Process interface concept
The responsible parties from Air Liquide opted for the process interface concept from Phoenix Contact. The Process Interface system consists of modular basic terminal blocks having a width of only 12.4 mm, and pluggable and codable electronic modules, also with a width of 12.4 mm.
Until now, conventional Ex-i interface components have been used for the Ex-i isolation, whereby the master cables leaving the Ex area were originally wired and jumpered with modular terminal blocks.
1 Test sockets
2. Clear labeling
3. Knife disconnection
4. Clear labeling
5. Automatic coding when the electronic components
are installed
6 Bridgeable supply voltage
7. Optional: With integrated surge protection, equipotential bonding contact to the DIN rail
The process interface concept allows combining Ex-isolation with input terminal blocks. As a result, a complete DIN rail with modular terminal blocks can be spared. Not only does this reduce the space requirement considerably, but also the possible sources of faults.
The integrated disconnect knives and test sockets allow problem-free isolation of Ex-i cables. Commissioning is therefore simplified considerably and the pluggability of Ex-i modules makes further functional adaptations easier.
In addition to the Process Interface and Varioface interface modules, Air Liquide has used other components from Phoenix Contact, such as power supplies, modular terminal blocks, shield connections and fuse terminal blocks.
Summary
