Calibration · Glossary

What is a Five Point Calibration?

0, 25, 50, 75, 100 %Calibration

A five point calibration checks an instrument at 0, 25, 50, 75 and 100 % of range, usually rising and falling.

Five Point Calibration Explained

Five points reveal zero, span, linearity and, with up and down runs, hysteresis. Three points are sometimes used for routine checks; ten or more for high accuracy work.

Approach each point from one direction without overshoot, and let readings settle.

Five Point Calibration Formula

Test point = LRV + p × (URV − LRV)

p	0, 0.25, 0.5, 0.75, 1

Example: Range 0 to 16 bar: 0, 4, 8, 12, 16 bar, expected 4, 8, 12, 16, 20 mA.

Calculators for Five Point Calibration

CalculatorCalibration Test Points GeneratorFree online calculator with formula and worked example.CalculatorHysteresis CalculatorFree online calculator with formula and worked example.

Free Downloads

Free downloadPressure Transmitter Calibration Report FormatFree download in Excel and PDF.Free downloadPressure Transmitter Calibration SOPFree step by step procedure, Word and PDF.Free downloadDP Transmitter Calibration SOP with Manifold SequenceFree step by step procedure, Word and PDF.

Frequently Asked Questions

What is a Five Point Calibration?

A five point calibration checks an instrument at 0, 25, 50, 75 and 100 % of range, usually rising and falling.

Why test downscale too?

To find hysteresis, which upscale only tests miss.

Is 3 points enough?

For many routine checks, yes; follow your procedure.

Learn more on the blog

Level transmitter 5 point calibration: as found and as left procedure

A practical guide on instrumentationblog.in with more detail on five point calibration and how it is applied on real plants.

Read Full Article

More Calibration Terms

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