Calibration Test Points Generator
Generate the test points for a transmitter or gauge calibration with the expected output at each point. Print the page to get a ready to use sheet with blank as found and as left columns.
Calibration sheet
| No. | Percent | Input | Expected output | As found | As left |
|---|---|---|---|---|---|
| 1 | 0 % | 0 | 4.000 mA | ||
| 2 | 25 % | 4 | 8.000 mA | ||
| 3 | 50 % | 8 | 12.000 mA | ||
| 4 | 75 % | 12 | 16.000 mA | ||
| 5 | 100 % | 16 | 20.000 mA | ||
| 6 | 75 % | 12 | 16.000 mA | ||
| 7 | 50 % | 8 | 12.000 mA | ||
| 8 | 25 % | 4 | 8.000 mA | ||
| 9 | 0 % | 0 | 4.000 mA |
Choosing Calibration Test Points
A 5 point check at 0, 25, 50, 75 and 100 % is the most common routine calibration. It reveals zero, span and linearity errors with little effort. Critical or custody transfer instruments often use 11 points.
Testing downscale as well as upscale shows hysteresis: the difference between readings taken with rising and falling input at the same point. Mechanical gauges and DP cells with high static pressure are most prone to it.
Expected output = Outmin + Percent × (Outmax − Outmin) ÷ 100
Frequently Asked Questions
How many points should a transmitter calibration have?
Five points (0, 25, 50, 75, 100 %) is standard for routine work. Three points can be enough for simple checks; eleven points are used for high accuracy or linearity testing.
Why test upscale and downscale?
Comparing rising and falling readings at the same point measures hysteresis, which a single direction test cannot detect.
Can I use this for pressure gauges?
Yes. Choose "Same as input" as the output so the expected reading equals the applied pressure.
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