Trending Data Through Video

Traditional trending was done on circular charts or strip charts. Circular charts were favored for easy storage of data from each shift, day, week, even month. Strip charts are linear, but only a small portion can be viewed at any one time. Of course, every system handles trends unique to the design of that particular vendor. Very easy and economical video trending is now allowing many more values in a process to be recorded. This chapter focuses on analog value trending and discrete value trending. The cursor can be moved over analog and discrete traces to make accurate comparisons at any given time sample. Trended, historical, and archived data do not carry the same degree of urgency as alarmed and operating data. The movement of historical data from distant stations will carry a much lower priority in the data management of the “process operating network”.