What is Historian, Pi System?

how its saved, that is all determined in the programs, as well as the scan rate.

In a process, when on the start up we had the scan cycle to save about every 5 seconds for trouble shooting on start-up. Unfortunately, no one wants to change it, and we have a $#itload of data. I tried to get them to spread it out to a more reasonable record now that we have solid control on the process.

The types of data we collect is flow rates, temperature, pressure. If we have a yield drop, we can track it pretty good on the machine.

Its great, we have it incorporated in out production reports. Saves a lot of manual redundancy.

Thank you for your comment, phoenix911.

Oh I understand that it is good to set the scan rate for each operation phase, such as startup. I will research more in that point of view.

Other information also help me a lot. I will make another thread when I have another question about this.

This will get old really fast.

OSIsoft PI System - Real-time data and event infrastructure ...

Start by searching for basic information, or visit the reference desk at the library.
The internet can provide mountains of information. Asking the forum to distill it and give you the crux is poor form.

Thank your for tips. As you mentioned, I should have asked a more specific question by describing what I understood before. I will make another thread after I summerize what I would ask.

DCS systems should have their own historian to allow researching "what went wrong" with the previous day's or even the previous month's events. Say the unit trips... they can go back and determine what went wrong. Was it operator error? Was it a failed valve? What happened to cause the issue?

If the historian lacks enough information, PI can help. It can be installed in a system to monitor and record a lot of points or variables. It can be tailored to suit the client (purchaser) with a few points or nearly any amount of points provided the point has a positive feedback.

Most new DCS systems should already have this covered, but some may not. In deciding to purchase a DCS system, the client or agent whose job it is to determine such should do his homework and assess the system being purchased as to whether or not it will be satisfactory. If the historian is insufficient, a PI system may be the easiest and most cost effective way to go.