Calibration

Calibration is checking the balance with a reliable weight standard.

Calibration answers the question: how accurate is the scale? The result of calibration is the determination of the error and uncertainty of the balance.

The error is the difference between the standard mass value and the scale's indication. Uncertainty defines the scatter limits of the determined measurement error.

A reliable mass standard is a standard checked with traceability, i.e. there must be an uninterrupted chain of references to a national or international standard. In practice, it must be a mass standard with a valid calibration certificate

Calibration is used to assess the condition and suitability of the balance for measurement tasks.

In addition, calibration enables the calculation of error and uncertainty of measurements made with this balance.

Calibration determines the actual accuracy of a balance, which can be used to assess its usefulness and technical condition.

The direct reason for the use of calibration is the requirements of quality systems such as ISO.

The PN-EN ISO 9001 February 2009 standard says that:

7.6 Where it is necessary to ensure reliable results, measuring equipment should be calibrated and/or checked at specified intervals or before use against measurement standards linked to international or national measurement standards.

Calibration is usually performed by an accredited measurement laboratory. Measurements are performed by qualified laboratory staff according to established procedures in strictly defined conditions (temperature, humidity, pressure, etc.).

However, there are no obstacles to doing it yourself!

An indispensable tool for balance calibration is one or several mass standards including values ​​(calibration points) for which calibration will be performed. Usually, they are Min, 50% Max and Max for the calibrated weight.

You need to know the errors and uncertainty of these mass standards (they are written on the calibration certificates).

You also need the value of the scale's reading division.

We perform a series of measurements, noting the scale's indications.

We substitute into the formulas and calculate the error and uncertainty. We do it for each calibration point separately.

A simple download.

Using the program, calibrations are performed separately at each calibration point.

When entering mass standards for a given calibration point, make sure that the standard or the sum of standards coincides with the current calibration point.

The measurement results (we recommend 10 measurements) should be written down from the balance. The transition to the next measurement takes place after pressing the Enter key twice (it works faster than the mouse).

After performing the calibration for all planned calibration points, you can generate a Report in the form of a table. This table can be copied to an Excel sheet and any necessary elements of the calibration certificate can be added there (company lettering, descriptions, signatures, etc.).

GOOD LUCK!