Tag limit?

I am considering the product FactorySQL.
What is the limit for number of tags that can be used (bidirectional) in the system?
100.000? 1 million?

How many tags have been tested “live” with this system?

You might want to look at the following white paper:

http://www.inductiveautomation.com/products/whitepapers/IABenchmarkWhitepaper2008.pdf

This gives a detailed look at testing carried out by Inductive to determine the kind of throughput in tags that can be achieved with a number of different databases.

The bottom line is unless you are in the tiny percentage of integrators putting in huge systems, the tag throughput becomes irrelevant. Steve Hechtman (IA’s president) wrote a good paper recently comparing the use of dedicated process historians to general purpose relational databases. You can read it here.

Al

Thanks a lot for the answer and the links. Interesting reading.

We are integrators with pretty large systems. About 60.000 tags in some systems. That is why I was wondering if FactorySQL could be an alternative for us for logging and communication with the PLC’s.

I guess I have to try to get the answer.

By the way, are there other products that does the same as FactorySQL with even better specifications?

I’ve seen one or two other OPC to SQL bridges, but I’ve no direct experience of them. Comments I’ve seen indicate FactorySQL compares favourably in terms of ease of use.

When looking at the requirements of your system, remember that having 60,000 tags in your system may not require a throughput of 60,000 tags a second. Some points may change more slowly, reducing the throughput requirements. Also, big systems tend to be heavy on digitals, which are processed much more quickly than analogues.

For us as integrators, FactorySQL/PMI doesn’t primarily sell itself to us by being the biggest, fastest etc. It’s the other things like great support, no cost View nodes, easy View node setup and use of standard IT technology that matter most in the real world. It can be a bit tricky for non-integrators to configure, but for integrators its complete openness is great, allowing you to do pretty much whatever you want with it.

Al

When looking at the requirements of your system, remember that having 60,000 tags in your system may not require a throughput of 60,000 tags a second
Yes, you are absolutely right about that!

Thanks again for the anwer, I'll give it a try!

I am currently working on a live project with more then 36,000 tags, all with 1 second update times. I have been trying my hardest to bring the system to its knees, but no such luck. You have to remember that with IA, you can have 200,000 tags, but if only 1000 are changing, the load is actually almost equal to the amount of changing tags. Something very important to remember.