Learning outcomes
- Explain the key principles of historians and data quality.
- Carry out a structured practical check or configuration task.
- Recognise common faults, risks and evidence needed for diagnosis.
Module 13 · Lesson 2
Historians and data quality
Configure reliable historical collection, compression, timestamps, quality and retention.
Before you begin
Historian platform and representative process tags.
Safety: Use site procedures, approved test equipment and competent supervision. Never bypass a protection or interlock without formal control.
Step-by-step learning
- Choose scan/update rates based on process dynamics and use.
- Configure exception/deadband compression without losing significant events.
- Store quality and source time where supported.
- Test query, export, backup and retention behaviour.
Ian's practical tips:
- A flat trend can mean stable process, dead sensor or excessive compression—quality matters.
- Keep raw operational data separate from manually corrected reporting data.
Fault-finding questions
- What should be happening, and what evidence proves it?
- Where is the last known correct signal, voltage, state or process condition?
- What changed immediately before the fault?
- Can the system be divided into smaller testable sections?
Practical activity
Create a one-page test record for this lesson. Include expected values, measured results, equipment used, risks controlled, defects found and the final proven condition.