A question came into Control.com’s Automation List the other day, about strategies to convince management of the benefits of going with Foundation fieldbus (FF) or a DCS. The question:
We have two options at our hands, either to go for in vogue DCS, an easier option to adopt, or implement the Fieldbus, a novel concept. The problem lies in convincing the management which is more inclined to DCS because it is in use in contemporary industries.
Responses came back, which correctly pointed out that most current DCSs offer Foundation fieldbus digital communications as one of the ways to connect digital field devices into the system.
Emerson’s Jonas Berge had a great response, first noting that Foundation fieldbus is not novel, with the process manufacturing installations starting in 1997. In his posted response, Jonas writes:
FF has come along way over the past ten years. The specifications have been clarified, corrected, and complemented. Product implementations of the technology have been corrected and completed. Better tools have come to market. Procedures for project execution and practices for operations and maintenance have been established. It is far easier to be successful now than only a few years ago. Most major EPCs now have FF experience. Your management should not worry about “immaturity”.
You may wish to justify to your management on the following basis:
- Project savings
- Operations improvement
Here is a summary of why FF works so well for plants:
Project Savings
- Less wires, conduits, trays, terminations
- Multiple devices per bus
- Multiple signals per device
- MOV, MV, feedback etc.
- Reduced control room footprint
- Fewer I/O cards and barriers
- Fewer engineering drawings
- Multiple loops per drawing
- Faster loop check and commissioning
- Automatic ‘ring-out’
- Enables innovation…
- New classes of digital devices
Operation & Maintenance Improvement
- Better accuracy
- No precision lost in D/A & A/D
- High signal integrity
- Distortions can be detected
- More powerful diagnostics
- More current for devices
- Engineering unit
- Measure to sensor limits
- No range mismatch
- Stave off obsolescence
- Firmware download
- Easier device troubleshooting
- Remote Diagnostics
- Validity display and loop shut-down
- Signal status
- Predictive maintenance
- Diagnostics Alerts
- Easier replacement and servicing
- Fewer Connections
Contact me directly at jonas.berge (at) emerson.com
For an FF project to be a success it has to be planned, engineered, and designed correctly. If you follow old DCS practices for design, loop check, commissioning etc. all you will get is a more expensive DCS without new fieldbus benefits. However, if done correctly FF will deliver on the great promise of digital control and architecture. These practices have been worked out and fine tuned by leading automation vendors over thousands of projects the past ten years.