Honeywell Experion PKS online downloading


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In our plant we are using Honeywell DCS, Experion PKS, R301 Version with C300 controller. We have both foundation Fieldbus and HART type instruments.

When I try to modify and load any Analog Tag number online, the Tag number immediately goes offline for a moment till the download completes. The system is unable to update the data from the field till the download gets completed. In the case of digital I/O's the downloaded DI tag goes to offline. For example if we try to download a DI (running indication) of a pump, which is running, the Pumps stops automatically as the DCS sends stop command automatically during the start of downloading.

This means that we are unable to download any Tag numbers online. How to overcome this problem?
It is not clear what you were doing. If you did it from configuration studio, you should inactive first CM or SCM you want to modified (manually or auto).

If you just modified from station/face plate, such alarm setting or other configurable items that does not require to inactive the point, you can do it online.


My quiery is why do you want to inactivate the CM/SCM before downloading. Does it meant the System is not suitable for online loading
It depends on your download strategy and what you will download.

It is a good question and very fundamental. Not possible to answer in 1 or 2 pages. I need 2 weeks EPKS training to understand.

My background is HPM/LCN (20+ years) - and the approach on Experion I found totally different. Unlike lcn everything lives within a CM.

In lcn/hpm the control regime is often segregated - i.e. modification of cl programs are done independantly (something I prefer). It looks like your pump chart already exists and you have modified it by adding a DI - IOCHANNEL block to the cm. When you download to the controller you get a choice to set the control to active. I have the same issue - today I changed some logic on a duty standby arrangement - and had to be careful, by changing the pump duty to the pump cm not being worked on.The chart does go to bad/inactive for a few seconds before going to the active state. I know of no way around it.

The same are with AI points, also beware that with AI points is not to scale the AI within the card. set the scales 0-100 and use a regcalc block within the cm.(Otherwise to change the scal later you have to inactivate the whole card- and affect several cm's that may reference it !)

On a process that's always in use it can make mods & changes difficult. It's important to upload before you make any chane as your project chart may be severfal months old and when you download it's easy to overwrite any changes parameters on any block within that cm- e.g. alarm & control limits. If possible change a parmeter in station and upload - of course that's not always possible.

It's important to regularly upload your charts and update to project - I do it monthly and maintain the records via a spreadsheet.
Another issue is you have to be careful the way you structure your charts. Invariably you will save the chart either by checkpoint or export of the project file. On reload after say a poweer fail you coulwould reload the chart in state it was saved - i.e. process running - that chart would then possible start e.g. operate at a time say when there are several more charts to load and activate. Best to segregate the cm's - that is if your licence has sufficient space to allow you to do that. Keep start flags away from the main control regime that way you can make sure thet are in the off state for any process / regime change.

Another issue is that my predeecessor put several io on one chart. This has a serious knock on effect in terms of alarms and detail displays.

Again if poss keep io seperate from the control regime.

It almost smacks of going back to UCN control with AI / PID control independant of sequence or logic control. From y experience although I have not had the time to do this ,

I work at a site that uses both HPM, with the extensive useof CL. Experion requires a differant sort of administration and takes some getting used to... I spent a good time last year tidying up charts so that they were easier to follow.

Big charts are hard to fauk diagnose unless you have a very large plasma screen (which we haven't!)
I could go on . . . . .

Hope the info helps . . . . .
We are facing similar kinda situation.

We have Experion PKS R210 servers installed at our site. They act as SCADA on front end of the control system. Backend is of Elsag Bailey Infi90. The two are linked together by Rovisys OPC 90 server. (this setup was made after the spares of Bailey consoles became out obsolete and spares werent available).

Now whenever a controller point is downloaded, the system kinda hangs up. All the stations show "????" in place of PVs of tags. Situation is brough to normal by refreshing the controler/channels that have been made in experion.

Also the systems become very sluggish slow after sometime (4 months approx). and gets okay when the servers are switched over (server A to B or vice versa).

Can anyone help me with this? Honeywell Technical assistance has been of no help. They cant find any root cause of the problem, let alone the solution!
You have several avenues of support.

You can contact your Honeywell sales people and demand that Tech Support help you. But since you have a Rovisys OPC gateway/server, you may not get help from Honeywell, and possibly rightly. It may not be their problem.

You can contact Rovisys.

You can also contact ABB, which is the successor company to Elsag Bailey and get help from them.

Walt Boyes
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Everyone has been contacted and paid to do something! but they don't seem to find any cause/solution of this problem.
No , it is not possible for on-line downloading for modification for particular CM/SCM. CM/SCM go off-line when you are downloading
I am perplexed that you are experiencing these problems. I have downloaded many DEVCTL points that had pumps running without impacting their run state. The same applies for valves; they have always retained their state. I was using PM I/O in all cases.

Only problems I encountered during a download from Control Builder were STIM/DE points, all other point types worked flawlessly.
It is not required to set the Fail Safe Status to HOLD, the download process should not result in a change of state. Again, I have never observed this and I have downloaded many a DEVCTL points online. I always get nervous when I do it, but it has never changed state during a download.
I just wanted to add my 10 cents worth on this issue. First of all your server really needs to be cleaned up on a regular basis-- I'm not too sure if some of the cache might need cleaning out-- you can setup a shell to do this-- sounds like this could be the issue as you have stated that after you switch over servers the problems seems to evaporate.

I'd employ a network monitoring solution to help you in this regard as you seem to have collision issues on your network. Just a suggestion mind you.

We are also using Honeywell's Experion PKS, R301 with C300 controllers on a few of our units and that problem was noted a few months ago.

The problem lies in the CM. In older HPM/LCN type DCS the logic blocks and DEVCTL blocks etc. existed separately to your outputs and inputs. In this system they are all lumped together in the CM. If your design engineer did not choose to pull these out and put them in separate CMs it means that everytime you make a logic change you are actually re-loading your I/O as well.

Apart from that you may try to change the CEE restart option in your CM to ALWAYS WARM which should hopefully tell the C300 to hold the outputs in their current position during a re-load. We have made these changes OFFLINE but are waiting for the best moment to make a mass download on all our CMs so in the future I will be able to tell you if that helped.
Well to clear things off, a CM with a DEVCTL block can be re-loaded without the valve/pump actually changing its state. The logic behind the DEVCTL holding the last value is Initialization, settled be parameter INITOPOPT=HOLDOPOPT. The DOCHANNEL block during its inactive state has INITREQ=ON that initialises the DEVCTL block with its previous value. The same it true with respect to AO_CHANNEL drivers.

I hope this gives some insight into the above

First of all the difference between TPS & EPKS:

1. In TPS we build separate points for DEVCTL/REGCTL/LOGIC/DIG COMP (called soft points, HPM resident) apart from their I/O points (hard points, which are hardware referenced) which are configured in the I/O modules.

Hence, any modification of logic if done, it calls for the soft point modification. Downloading that point needs that it is "inactive", and after download it is to be turned back to "active". In this deal, the I/O point (hard point) remains "active" holding the last state (if configured) of its input/output as the case may be.

2. In EPKS we build CM (analogous to TPS point). The biggest mistake which is done here is when we include the I/O channel (DI/DO/AI/AO) in that CM.

When this CM (including the I/O channel block) is downloaded the CM is turned "inactive" and back to "active" after download AUTOMATICALLY. (similar to TPS where it is done manually by engineer).
The problem lies here, when the I/O channel (which is CM resident along with logic) also goes inactive (turning the DO OFF or AO to 4mA).

In TPS nobody complained about online download was because, all the I/O points (hard points) were configured with BADCTLOPT/BADPVOPT parameter as SHEDHOLD.

Due to this, whenever the DEVCTL/REG CTL/LOGIC point (soft point) was downloaded and inactivated, the I/O point would hold its last state till the point is activated back.
Hence, this was possible.

Similarly, in EPKS build seperate CMs for I/O channel, LOGIC/REGCTL/DEVCTL. Configured the BADCTLOPT/BADPVOPT of I/O channel to SHEDHOLD, and you can easily do any modification you want.

Probably, to save the cost of system license the engineering is done this way. Since, in EPKS the no. of PROCESS POINTS are licensed.
In TPS the hardware used (NIM) was capable to hold 8000 points.

Try build seperate CM for logic and I/O channel and enjoy the online modifications.