Measurement review

Repeat before changing the calibration

The third block has a wider range. Repeat with unchanged calibration before treating it as a persistent change.

Illustrative sensor readings from one bench session
Block Readings (mV) Range (mV)
First 10.1, 10.2, 10.0, 10.1 0.2
Second 10.2, 10.1, 10.3, 10.2 0.2
Third 9.7, 10.5, 10.0, 10.6 0.9

How should the repeat be sampled?

Keep the sensor, calibration and interval fixed. Four readings match the earlier blocks; eight give more evidence about the range.

Four readings · two minutes Eight readings · four minutes