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Controls › Instrumentation

Calibration

Proving an instrument reads correctly and recording that you did.

4 topics4 written guides

Written guides in this section

Full references, procedures, and diagnostic guides published under Calibration.

ReferenceInstrumentationCommissioning

Calibration Procedures

How a utility calibrates its instruments consistently: the as-found and as-left discipline, tolerance from the loop rather than the data sheet, the reference standard and its traceability, the five-point check with hysteresis, adjusting only when needed, intervals set from history, and the procedure written once per instrument type.

9 min readUpdated Sep 5, 2026

ReferenceCommissioningInstrumentation

Loop Checks

Proving every I/O point end to end before a system goes live: what a loop check is and is not, the three-point analog check, discrete and output checks, the two-person method with the sheet that records it, what to do with a point that fails, and why a loop check is not a calibration.

9 min readUpdated Sep 5, 2026

ReferenceInstrumentationDocumentation

Calibration Documentation

The records a calibration program produces and what each is for: the calibration certificate per event, the instrument history, the reference standard file, the schedule, the tolerance and interval register, and how the records are organized so a regulator, an auditor, or the next technician can find what they need.

8 min readUpdated Sep 5, 2026

ReferenceInstrumentationCommissioning

Calibration Troubleshooting

When an instrument will not calibrate or stay calibrated: wrong or expired standards, slope and offset out of range, compensation errors, procedure mistakes, loop scaling that disagrees with the instrument, and deciding when to adjust, replace.

8 min readUpdated Sep 5, 2026

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