Production replay - shows what really happened

Normally you do not know the problems in the production until afterwards. The Production Replay tool in the FirstOpNet client makes it possible to analyze the problems several months back in time.

The internal signal database is continously saved in local compressed binary files in high time resolution down to 50 msec resolution. The files contain all data, including analog and logical signals. This means that you can display the exact sequence of events that lead up to the situation you want to analyze. Moreover, you have access to all signals since you often do not know beforehand exactly which data you need.

The Production replay tool was first installed in the new Cold Rolling Mill MA700 in Outokumpu Stainless, Långshyttan, Sweden which was delivered by Mitsubishi-Hitachi. It turned out to be an invaluable tool during comissioning. Any event or malfunction in the mill could be analyzed in detail afterwards, see above.

The graph above  displays four passes in a cold rolling mill at Outokumpu Stainless in Långshyttan, Sweden. By the zoom function, indicated by the square in the middle, you can investigate details down to 50 msec in this case. Totally, there are about 1100 logical and real signal values that can be displayed in this way. All production in the mill during one year has taken about 30 Gb local disc space.

Function summary

• The whole local database is stored in compressed files with time resolution down to 50 msec
• A special software tool TimeLog is used to unpack and display databas signals in curve graphs
• Any signal in the local database can be displayed in detail afterwards
• Any event in production can be retrieved and analyzed several months back in time