· Manie Maritz
Updated
What drives PI System TCO after the first licence
PI System and AVEVA Historian are different products with different licence shapes. When tag count, client seats or renewal terms outpace what the plant uses, re-run the numbers against your own tag list — including TDengine Historian beside or instead of PI.
AVEVA PI System is mature and familiar on many large sites. Growth cost is usually tied to tag count, named-user clients and add-on modules — not to a single line item on the first quote.
It is not Wonderware. AVEVA Historian — still called Wonderware Historian on many South African plants — is the SQL Server-based process historian that sits with InTouch HMI and System Platform. PI System is the former OSIsoft stack (PI Server / Data Archive, Asset Framework, optional PI Vision) that AVEVA acquired in 2021. AVEVA still sells both. Mixing the names leads to the wrong commercial comparison and the wrong migration plan.
The cost shape that hurts
The problem is rarely the first invoice. It is the shape of the curve after it.
On PI, cost has historically grown with tag count, named-user clients and add-on modules (PI Vision, PI DataLink, PI Integrator and others). Many new AVEVA deals run on Flex credits — a subscription currency across PI, AVEVA Historian, InTouch and System Platform — but plants on perpetual licences and support renewals still need a quote against their own tag list and contract terms, not a published rate card. Either way, the number to compare is the one scoped against what operations actually trends, reports on and alarms on.
We deliberately do not publish a comparison table. Licensing on both sides moves, and tag-tier figures repeated out of context are usually stale by the time anyone reads them. The number that matters is the one built against your own tag count, user count, connectors, redundancy requirement and support terms.
What most plants actually need from a historian
Most South African plants do not need every niche PI add-on on day one. They need:
- Reliable ingest from PLC/SCADA and telemetry
- Long retention without thinning tags to fit a licence tier
- Dashboards and reports operations teams will actually use
- A path that does not demand a weekend rip-and-replace — TDengine can sit beside PI while the numbers are proven
How LCT approaches evaluations
We run proof-of-concept work that compares your real tag shapes, retention needs and report outputs — not brochure feature checklists. If PI remains the right answer, we will say so. If TDengine Historian (TSDB + IDMP) can cover the storage, asset context, dashboards and reports you depend on, we will quote it against your tag list — with PI still live beside it if that is the safer path.
The capability comparison is set out on TDengine as a PI System alternative, and the phased approach that keeps PI live while TDengine is populated alongside it is on PI System to TDengine migration.