Temperature drift, weighing

The temperature dependence of the calibration error (temperature drift) is tested in new balances at the factory. Test weighings are made in an environmental test chamber at various temperatures (e.g., 10, 20, and 30 °C). A typical tolerance for the span drift (sensitivity drift) as a function of temperature for an analytical balance is 1 ppm/ °C, also expressed as I0 /°C. With a test weight of lOOg, this means that a correct reading of 100.0000 g at 20 °C could change to 99.9999 g or 100.0001 g (or anywhere in between) if the temperature were to change to either 19 or 21 °C. 

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