Fisher NPS 1 GX with DVC6200F Foundation Fieldbus Test

Good day. I am dealing with a foundation fieldbus digital valve controller (DVC6200f) on a fisher NPS 1 GX. The connection of the devices to a Foundation Fieldbus network is not in our scope, but it is important to have this valve operate to test. Is it the only way to have a FF host and connect the valve on the network, or are there other ways to "simulate" the valve? I have access to a 475 Communicator.
 
Warning, I can't answer your question, other than the obvious that for a test the actuator needs air and the FF positioner needs FF power; I just want to rant about Foundation Fieldbus.

A couple years ago, just before Covid, I spent 40 days in the wilderness learning how to do some very basic Foundation Fieldbus operations with a Softing modem and Pactware Windows software in order to assign a device address and a tag name to a hundred FF field transmitters. Whew. Figuring out the process was brutal. The process is/was so arcane, I can scarcely recall it, it was so arbitrary.

I ended up with a 30 page power point with dozens of screen shots with incremental step instructions for just two simple tasks, device address and tag name, so that a hireling could work his way through the actual configuration task.

The process involved tasks like adding a device, selecting a DTM, making the connection, re-establishing the connection, discovering the undefined, magical "Show Live List" function, matching default node address with initial target address, ya-da, ya-da, ya-da.

If any step was missed, no connection, no comm, nothing. Brutal.

Maybe the 475 integrates a lot of what a software/modem package does not. I don't know. I looked into renting a 475 for the task, but the vagaries of rental, where the rental house could not define whether the DTMs I needed were installed or not, which is huge deal for a now-unsupported device, the 475, that needs the exact DTM. The rental houses expected the user to figure out how to add a DTM to an unsupported 475. I took a pass on the 475 and took the Softing modem/Pactware approach (I'm familiar with the basics of Pactware running HART DTMs, which proved to have little carry over; either uses the 'connect' button)

There is an incredible void of practical support material for FF. Lots of old marketing/sales BS youtube videos telling you how much money it saves, how the control architecture can skip the PID control block in the DCS and move it to the flow transmitter (anyone get trampled in that rush?) but precious little that opens the door on the mysteries of a very complicated protocol.

There is one great youtube video on commissioning FF in a Delta V DCS that uses a 475.
Ian Jappy does a great job. I love the video because it details the 15 step process of commissioning a single transmitter, which includes a Capacitance check, of all things. When FF was 'the best thing since sliced bread' in the 1990's, all the BS was how easy it was to commission because FF's digital reporting eliminated the dreaded loop test, 4mA, 20mA, 12mA and the associated engineering units check. Yeah, with FF, the loop test isn't needed, but a wiring capacitance check is (static check, 3:40), but the resolution of an out-of-tolerance capacitance value was not addressed in the video. But the video does show a clipboard with a whole page checklist of tasks (5:21) needed to commission one FF transmitter, easily equal to, if not greater in magnitude, than that needed for 4-20mA commissioning. And Ian used a Fluke 123 handheld scope to check the FF digital signal waveform (12:10), something 4-20mA has managed to avoid for 60+ years.

I would think that something as 'smart' as a 475 would recognize FF commissioned instruments, their device addresses and tags and let you run a manual mode test on a positioner, maybe ? ? ? If you can find where the manual mode command is buried. Oh, Ian mentions the OOS (out of service) mode and that it varies from the HART OOS mode, but that might bear some research on if you're doing manual mode tasks.

Ian uses the 475 to look at the device list at 26:00 and a simulation at 27:04, so you can skip the loop check, oops, I mean segment check, in the early part of the video. For something as complicated as FF it might pay to watch the whole thing.

If you figure it all out, please write it up and post it here, on this forum, it would greatly benefit the controls community and get a "Like" from me, even if I'll never have to do it, now being retired.
 
Assuming your 475 supports FF (and has the DD files for the DVC6200f), you should be able to setup a test segment, it can act as the FF host. For the segment you could use a Relcom Power Hub "Fieldbus Segment in a Box" or similar: https://www.relcominc.com/power-hub , you would connect both the DVC and 475 to the Power Hub.

Then I would expect you would need to "commission" the DVC, that is, assign it a "permanent" address (VALUE < 248) using the 475. Then the Transducer block should be accessible; it's mode probably needs to be set to Manual to conduct a Valve Stroke Test (FST/PST). Interestingly, the manual says this: "Note FST/PST is only available with a PST instrument."

You would no doubt have to spend some quality time with the [350 page] instruction manual to understand the valve stroke parameters. When you are done with testing, it may be best to set the device address back to the default value [248] so that the DVC will appear as "un-commissioned" when it is installed in a real segment.

Note that I have never used a digital valve controller, all above information is theoretical based on general FF experience and a glance at the DVC manual.

I certainly agree that the Foundation Fieldbus is not user-friendly, and it is much too complicated.
 
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