RSBatch for discrete equipment

M

Thread Starter

moakdi

Hi all,and happy new year.
Maybe this is not the first time this question has been raised in this forum.

The company I work for produces medical devices, what means discrete machines in a highly controlled environment (full validations). We also use very flexible equipment and production often changes requirements. Some time you have to introduce a new piece of equipment in an already working and validated line (with an appropriate SQL recipe/reporting app.), sometimes it is a full new line from scratch, and some times it is stand alone equipment.

The type of equipment we build, it is not only discrete for the nature of the products we produce but also for the type of process we control (Often motion with an approx. cycle time of 30 to 90 sec per unit procedure). We where researching for an appropriate standard to base our own integration standard on (some short of naming convention and project frame to be use for all equipment), and obviously S88 came along due to the modularity and reusable capabilities (key points on validated systems).

We work closely with Rockwell (RW), to find the best way to approach a standard solution. RW strongly suggested the use of RSBatch together with Phase Manager (PLC Layer). We did our own investigation and we implemented equipment using Phase Manager and simulating a batch control server. We found numerous problems as the poor execution time of Phase Manager within the PLC, the implicit delay of running each phase (get ownership (1 Scan), reset (1 to 2 scans) , then run the phase and last, release ownership). We also found delays on commanding phases from the Batch Server application. We investigated a little bit more on how the diagnostic event works with the batch server by simulating a batch server through an ODBC connector.

We found that the diagnostic events generated on the HMI (FTalk SE) are difficult to filter and they supposed a massive load to the network. We also found some other problems as the lack of expertise on RSBatch, the network infrastructure on our site (we share the production and IT network, and for RSBatch to work a dedicate network would have to be implemented), the need of an extra server (and due to quality / validation requirements, an additional server per each new independent equipment, or revalidation of existing servers), difficult integration with existing SQL based systems.

We are in a point where we are convinced that S88 is the way to go, and to prove it we developed a custom application using RW PLC/HMI and a SQL DB, where we developed our own phase manager functionality with AOI and Control Module library. Now we have to decide on the future. We have explained all our experiences to RW but they still insist that RSBatch is the way to go. We have asked them if they got any references of end customers using RSBatch for discrete machine and they told us "YES" but we are still waiting for those references.

I would like to believe that RSBatch is actually suitable for discrete equipment and not custom code is needed, but in order to prove so, an enormous investment and afford will be needed (including IT resources). Sorry about the long post, but at this point the question is pretty obvious, HAS ANY BODY OUT THERE EXPERIENCED DISCRETE/FLEXIBLE SYSETMS USING RSBATCH? (or other type of batch server applications), WOULD YOU RECOMMEND IT?
 
I think PLC cannot do that easily. If you really need to do that I think you should use DeltaV. It is easy to apply this in DeltaV system. But if you really need to apply this in PLC, I think there should be some way to do that.
 
I don't see many replies to your question about whether anyone is using RSBatch for your type of application, so I think it is likely that the answer is "no".

I don't have any direct experience in your industry, but I will say that the configuration you have sounds like a lot of complexity for little or no gain. Validation of the process is a major bottleneck to changing anything significant, so you shouldn't be doing program or parameter changes on on a daily basis.

I suspect that what you really need is a conventional PLC configuration together with a networked PLC program version control system. There are a number of systems that do that, and if I recall correctly, AB bought (and now sells) one of the better ones.

I think the idea of SP88 is to let you make major configuration changes on a batch to batch basis in order to balance the use of interconnected equipment. This is probably the opposite to what you need. I would think that what you would really want to do is to check if anything has been changed in the PLC since it was last validated for that product. Or to put it another way, you would download the validated program from the version control system as part of the change over, and then simply run it.

As for what advice Rockwell has been giving you, well take it with a grain of salt. They will be the experts on their own products. You're the expert on your manufacturing process. If you are looking for references, the time to ask is before you commit to a purchase, not after.
 
I hate to disagree, but I do.

ISA88 is about procedurally based manufacturing. That can be the traditional recipe/batch methodology originally considered, but it applies to all procedurally based manufacturing with great facility.

There were several papers about using ISA88 and RSBatch in discrete industries presented at the last couple of WBF Conferences. They certainly indicated good success, and as far as I know there is no reason why you could not do this.

This is why the original ISA88 team segued so quickly into ISA95, to develop a manufacturing language for all manufacturing processes, not just batch.

Even WBF is no longer solely interested in batch manufacturing.

Walt Boyes
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In reply to Walt Boyes: I assume you are disagreeing with me. Would you care to elaborate on your point?

Are you simply saying that you have heard that someone else has already done it? If so, well we already know that "moakdi" did and wasn't entirely happy with the results.

Or are you saying you think that SP88 with RSBatch is a good way to implement discrete assembly type manufacturing? In this case, is that you just like the concept, or can you give a practical application?
 
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