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Module · Data Logger

Data Logger — plant history and trends

The historian that records how data evolves over time. It writes to a local file or an enterprise database and prevents data loss during outages with store-and-forward.

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MergenHub — Data LoggerConnected
MergenHub — Data Logger

The MergenHub interface — the module's live view, running in the browser.

What it does

Data Logger records the values of selected tags periodically or on change. It offers an install-free historian with local SQLite, or writing into your existing enterprise database over ODBC. Logged data is displayed in trend charts and exported.

Key features

Store-and-forward buffers data when the connection drops and writes it when it returns. Downsampling controls data volume over long intervals. Export to PNG/Excel/CSV from the trend screen.

Module

Core capabilities

Sink

SQLite / ODBC

Install-free embedded SQLite or an enterprise ODBC database (three DB engines) as targets.

Reliability

Store-and-forward

When the connection drops, data is held locally and forwarded automatically when the target returns — no loss.

Volume

Downsampling

Sample thinning over long intervals to manage data volume and disk usage.

Visualization

Trend charts

Multi-tag trend charts over historian data with zoom and time-range selection.

Export

CSV / Excel / PNG

Export trend data as CSV, Excel or PNG for reporting.

Triggering

Periodic / on change

Log on time interval or on value change; per-tag configuration.