Calibration Weights are used to check the reading of scale, to make sure it is still accurate. They used when calibrating a scale.
While the calibration states how a scale behaves, adjustment of the scale changes its behavior. What it dose is a set of operations carried out on a scale so that it provides prescribed indications corresponding to given values of a quantity to be measured.
Therefore, adjusting a scale means modifying its indications in a way that allows them to correspond – as much as possible – to the quantity values of the measurement standards applied.
Class 0 - Used as a primary reference for calibrating other reference standards and weights. Class 0 weights are intended to be used in metrology laboratories where the stability of the environment and careful handling are assured. Although very stable, one-piece construction Class 0 weights have no method of adjustment and are not suitable for general laboratory use. The uncertainty is guaranteed to be 1/3 the tolerance.
Class 1 - Can be used as a reference standard in calibrating other weights and is appropriate for calibrating high-precision analytical balances with a readability as low as 0.1 mg to 0.01 mg.
Class 2 - Appropriate for calibrating high-precision top loading balances with a readability as low as 0.01 g to 0.001 g.
Class 3 - Appropriate for calibrating high-precision top loading balances with a readability as low as 0.01 g to 0.001 g.
Class 4 - For calibration of semi-analytical balances and for student use..
Class 5 - (Class F) Primarily used to test commercial weighing devices by state and local weights and measures, device installers, and service technicians.
Class 6 - For rough weighing operations in physical and chemical laboratories, such as force ..
Class 7 - For rough weighing operations in physical and chemical laboratories, such as force ..
Class F - (Class 5) - Primarily used to test commercial weighing devices by state and local weights and measures, device installers, and service technicians.
OIML Calibration Weights
OIML Class E1 - OIML Class E1 Weights manufactured to international recommendation, OIML R111 specifications would be used to calibrate Class I/II balances, balances accurate as 0.001mg, and as a laboratory standard. These classes are considered to be of extra-fine accuracy.
OIML Class E2 - OIML Class E2 Weights manufactured to international recommendation, OIML R111 specifications would be used to calibrate Class I/II balances, balances accurate as 0.001mg, and as a laboratory standard. These classes are considered to be of extra-fine accuracy.
OIML Class F1 - OIML Class F1 Suitable for use for traceability of OIML class F2 weights and lower; also with OIML accuracy class I weighing instruments. The maximum permissible error from nominal value at 1 kg is ±5 mg. For the calibration of high accuracy class 2 balances.
OIML Class F2 - OIML Class F2 Suitable for use for traceability of OIML class M1 weights and lower; also with OIML accuracy class II weighing instruments. Intended for use in high value commercial transactions such as gold and precious stones. The maximum permissible error from nominal value at 1 kg is ±16 mg. Used as working standards for precision and analytical work, build-in weights, external weights to calibrate moderate precision balance
OIML Class M1 - OIML Class M1 Suitable for use for traceability of OIML class M2 weights and lower; also with OIML accuracy class II weighing instruments. The maximum permissible error from nominal value at 1 kg is ±50 mg.
OIML Class M2 - OIML Class M2 Suitable for use for traceability of OIML class M3 weights; also with OIML accuracy class III weighing instruments. Intended for use in normal commercial transactions where goods are sold by weight. The maximum permissible error from nominal value at 1 kg is ±160 mg. Used for accuracy class III applications, industrial scales, dial scales, trip balances, platform scales