Scales are measuring tool and are designed to calculate weight. Weight is measured by such a unit as a kilogram, as well as its derivatives, such as ton, milligram, etc. Due to the fact that exactly weight measure is unrealistic, the results of calculations of weights to be accurate with a certain measurement error. On the other hand, the testimony of the weighing results in the display of electronic scales are displayed some discrete, denoted by the value d. For example, the display shows the trade weights 1 kg, by adding a weight of 3 g of readings will be equal to 1.005 kg, ie will vary with a step d = 5, many think that this quantity d is the measurement error weight. But it is not. Maximum permissible error of measurement determined by the price verification scale – a special metrological value is, usually the manufacturer of weights guarantees the following relationship: d = e.
This equality allows us to establish a link between discrete readings and measurement error. Besides having important metrological characteristics are the largest (NIP) and the smallest (NmPV) limits weighing. Outside these limits testimony weights are not always correct. Electronic scales precision measurements can not be with a larger value of the nip. Decide first that matters to you. For accurate weighing should stay on the scales with a smaller value of e and a small ivc, respectively. On the choice of model affects several functional features: a set of functions implemented in the weights, constructive (external or internal cooling fan, the size of the platform, overload protection, etc.), an interface, a type of food, environments – some models are available in a higher dust-and waterproof performance or with a load cell and a platform made of stainless steel.
When you select a check to see whether you need a function to standard or options. As an example of neglect by weight metrology measurements can be reduced literal use of the consumer so-called counting function of the weights. This function is implemented in counting scales cas models, cs, sc, ac and is a two-stage process of first determining the average weight of identical parts (by weighing samples from them a certain amount), and then – an unknown number of them in the working portion of its weight. In the advertising material is lead up the accounts up to pieces, without specifying what the real error accounts in pieces. It is clear that the claimed accuracy – the formal results obtained by the microprocessor weights when performing an arithmetic division operation. Thus, the interpretation of measurement results should be an expert having knowledge related to mathematical statistics and possession of a priori information about statistical characteristics of the weighted products. Counting scales, in this case, play supporting role.