News from Profibus / Profinet – Part 9 How PROFIBUS Makes Network Planning a Breeze
Successfully planning and realizing a project with a fieldbus is different than implementing a signal transmission application involving 4...20 mA but is not more complicated. Nevertheless, it can be advantageous to have newcomers to fieldbus technology be accompanied by experienced users or planners when realizing your first project to ensure that the necessary adaptations and all additional possibilities and options are successfully taken into account from the outset.
The retired plant operators and maintenance and service per-
sonnel took a timeout to enjoy a fresh cup of coffee after having inspected “their” plant. The older man and the man with the beard now sat next to each other at a table and the youngster made small talk with them on his way to the podium.“That's not how the inspection tour should go”, he mentioned to the man with the beard. “After you moved the positioner to manual mode, you immediately toggled back to automatic mode.” “Didn't I tell you?”, the older man said in a loud but amusing tone, “He can't ever walk past a device without playing with it! But how did you notice this, and is the device really operating in automatic mode again?” “Yes it is”, responded the youngster. “I'll bring that up later on. Right now, however, I want to talk about network planning.”
Successfully planning and realizing a project with a fieldbus is different than implementing a signal transmission application involving 4...20 mA but is not more complicated. Nevertheless, it can be advantageous to have newcomers to fieldbus technology be accompanied by experienced users or planners when realizing your first project to ensure that the necessary adaptations and all additional possibilities and options are successfully taken into account from the outset. It goes without saying that engineering tools and control technology automate many process steps, and the benefits of using instrumentation together with PROFIBUS PA make the investment well worth it — from the time the plant is initially commissioned through to the end of its lifecycle.
Leveraging Flexibility for Maintenance and Expansion Measures
Ensuring the availability of a plant is one of the most important criteria that must be factored in during the planning stage. For example, when maintenance work is carried out for a single measuring transducer or the transducer is replaced, the functionality of all other devices and equipment in the system must not be compromised. This is easy to achieve with the PROFIBUS PA standard, even in areas with explosion protection. The simple topology, which has a trunk-and-spur configuration, is clearly arranged, easy to use, and makes it much less troublesome to provide verifiable proof of the level of explosion protection required during planning and installation. Existing devices can also be conveniently exchanged or replaced and additional devices integrated, even while the plant is operating.
Obtaining Better Measurement Results Using Fewer Measuring Points
PROFIBUS supports data transmission from multi-variable devices with high-resolution measurement data. This, in turn, provides the following benefits that are hard to achieve using 4...20 mA technology: The option of deploying fewer field devices while at the same time acquiring more information, lower investment costs, reduced planning and documentation outlay, and the possibility of running the plant in a much more efficient manner.
Fieldbus technology bridges the gap between control and measurement systems as measuring instruments are integrated into the control instrumentation environment and thus become part of the overall system. Users therefore have direct access to all functions and can make optimal use of the devices and plant, which ultimately leads to more streamlined and cost-effective operation.
The older man and the man with the beard could hardly wait for the youngster to return to their table after his speech. “Now I want you to finish explaining yourself”, mumbled the man with the beard, who somehow felt ill at ease. “How did you know that I played around with the positioner?” “I sent a text message to the control room before we embarked on our inspection tour and asked my colleagues to keep a sharp eye on the plant. They don't overlook anything!”, he answered with a grin on his face. “And to whom or what did you send the second text message?”, the older man inquired. “The second text message?”, the youngster asked surprised and somewhat perplexed.After a brief hesitation, he responded by saying that he sent it to the IT department and made it clear that he didn't want to offer any further details at this time...
To be continued: Part 10
Further parts of our Profibus series:
Part 1: PROFIBUS – a Proven Technology
Part 11: PROFINET for Process Automation
Watch the video to find out more about the young engineer, the older man, the man with the beard and PROFIBUS PA.