– Resolution (d) or dividing the price scale – the minimum amount that may change the weight readings. – Price verification scale (e) – conditional value, expressed in mass units. That's it characterizes the accuracy of the scales. Typically, the operation of e 10d. – GOST24104-1988-2001 GOST24104. Currently, there are two guests, in which all calibrated laboratory scales: GOST24104-1988-2001 and GOST24104, so the choice of weights in addition to accuracy class should be specified and the number of GOST. – Accuracy of weighing – the difference (x – a), where – given a number, which is regarded as an approximate value of a quantity whose exact value is equal to x. For laboratory balances by GOST 24104-2001 error in the measurement range in absolute value should not exceed the limits of permissible error.
Intervals for weighing scales of accuracy class limits permissible error special (I) High (II) medium (III) in the primary calibration for operation up to 50000e inc. to 5000E incl. to 500e inc. 0,5 e 1,0 e St. 200000e 50000e to inc. St. 5000E to 20000e inc. St.
500e to 2000e inc. 1,0 e 2,0 e St. Source: Sonny Perdue. 200000e St. 20000e St. 2000e 1,5 e 3,0 e Note: the weights with discrete reading device limits permissible error 0,5 e; 1,5 e; should be rounded to 1e; 2e, respectively. – Smallest weighing limit (NmPV) – the minimum mass that can be weighed in the scales of the model with guaranteed range the margin of error. The values of n (the number of verification scale, which are defined as LEL / e) and NmPV depending on the accuracy class weights and price verification scale e GOST 24104-2001 are shown in Table: Accuracy en NmPV special (I) any more than 50,000, and 100d high (II) to 50 mg inc. from 100 to 5000 incl. 20d St.. 50 mg of 5000 to an average 50d (III) to 2 g incl. from 100 to 10000 incl. 20d St.. 2d 500 to 10000 incl. 20d weights to certain requirements, regardless of their destination. These requirements can be divided into metrology, operational and health, but for laboratory balances preferred metrological requirements, which determine the quality of work balance. We select the most important of them – this is the accuracy of the weighing sensitivity, consistency and stability of readings. Accurate scales are considered when weighing the testimony they give to the deviation from the true readings within the margin of error. On the accuracy of laboratory balances can be divided into groups: – Analytical – scales with an accuracy greater than 0.1 mg – Precision – scales up from 1 g to 1 mg. You can also select some other properties and abilities: – The sensitivity of the scale – to leave the property equilibrium with a slight change in weight of cargo. In this case, the sensitivity of electronic scales is their discrete nature. – Sustainability – property weights in deriving them from the equilibrium state independently return to its original position after some hesitation. – Persistence of evidence – the ability to give the same testimony with multiple repeat weighings.