Choosing a process historian: a practical checklist

A process historian system collects time-series data from Programmable Logic Controllers (PLCs), Supervisory Control and Data Acquisition (SCADA) systems, and sensors. This data can be stored for long periods and accessed quickly for analysis and reporting. However, many organizations make mistakes when selecting a historian by comparing feature lists rather than assessing compatibility with their existing systems.

A proper selection process begins by evaluating the SCADA or connectivity layer and the analytics layer, followed by choosing a historian that integrates smoothly with both.

Built specifically for industrial applications, process historians are designed to handle large volumes of data, employ compression techniques to save space, and provide fast retrieval for trend analysis and reporting. Some notable options include:

- AVEVA PI System: a comprehensive solution offering enterprise-level operational data infrastructure.

- Canary Historian: focuses on lossless compression, fast trending, and straightforward tag-based licensing.

- Proficy Historian: part of the Proficy suite, used for archiving process data at both site and enterprise levels.

- FactoryTalk Historian: developed by Rockwell Automation, it gathers data from Logix and plant level machines.

- dataPARC: offers process data analytics and historian functionality, which is particularly popular in industries such as pulp and paper and chemicals.

Additionally, there are open or open-core time-series databases that can function as lightweight historians. Some examples are InfluxDB (by InfluxData) and TimescaleDB (a PostgreSQL extension for time-series and sensor data).

When selecting a process historian, it is essential to consider several key factors. First, determine how the existing data is collected (e.g., OPC server, SCADA, or MQTT) and whether the historian can read this data natively. Next, evaluate the licensing model, which could include per-tag, per-server, subscription, or open-source options.

Another crucial aspect is deciding the level of data management required, such as site-level, enterprise-level, or both. Furthermore, identify which analytics and business intelligence (BI) tools will be used to access the historian's data, as compatibility is essential for smooth operation. Finally, consider the administrative capabilities needed and the existing skill sets of the IT team.

For more information on process historians and integrations, refer to the PlantWired directory, a vendor-neutral resource that lists every historian supported by factory software. The guide also provides integration details and pricing information, but it is always recommended to confirm these details directly with the vendor. Corrections and feedback can be submitted in the comments section.