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Process industries or greatly instrumented industries produce, fabricate or transform products which, more and more require documentary evidence of the conditions in which they were done. Such evidence may be of a contractual nature with regards to its customers, of a normative/prescriptive order in certain industries, or of a strategic order in the case of a company’s strategic choice. Process Data Historian systems are becoming more and more necesssary to make progress regarding a better command of one’s techniques and fabrication processes.

Better exploiting one’s processes by using the strict minimum in optimum conditions, improving the quality of products and being able to prove fabrication conditions in the long or very long term, are strategic axes in order to obtain new markets and to obtain significant financial gains with regards to consumable goods. The implementation of a Process Data Historian system is often the first unavoidable step to later implement systems capable of exploiting it and transforming the data into interpretable information (eg, SPC, MES, graphics reconstruction, calculation, analysis).
Process Data Historian systems have 4 major objectives:
  To promote the command of resources which have a significant financial impact on production.
  To receive, centralise and make the process data available in the long term for its exploitation.
  To obtain reliable information on the acquisition process in order to make justified decisions.
  To favour preventative methods with a better control over drifts.

Process Data Historian systems are based on high performance technologies of acquisition and inscription. The capacity of volume of acquisition is great, generally in thousands, even in tens of thousands of variables being processed per second. Often relying on data compression engines, the capacity of inscription volume is great while minimising the physical space allocated to the different storage material. Logical data can be calculated and stored originating from physical data so as to stock only relevant data. The writing itself of the data is often subject to inscription conditions (at each change, sampling frequency, deadband, hysteresis, drifts). Process Data Historian systems are also justified by the need for availability; they are often the subject of attention by editors on the availability criteria and their associated architectures (redundancy).

Process Data Historian systems distribute withheld data to other systems or restoration tools. The restoration is conveyed in different types of graphics (curves, tables, spheres, sliding bars). The restoration often depends on the availability of the extraction criteria, the most common being of one or several data from date to date. Certain editors question such systems through external reporting tools to standard SQL (see reporting tool and Business Intelligence).