The wind tunnel development with wind speed control is presented in this paper using an ultrasonic anemometer. It were used the Time Difference and Phase Difference methods in the measurement of the air speed, and the circuit used for the measurement as for the speed control it was based on a microcontroller and an motor (fan). The experimental results obtained from the proposed circuit are compared with a commercial anemometer. The analysis of temporal response performance of the fan speed control circuit was developed to validate the proposed system.

Results of experiments concerning humidity measurements have been presented in the paper. Integrated humidity sensors were used for the experiments, which transformed the value measured into a corresponding capacity. The structure of a measuring system was described, and the requirements concerning particular elements of the measuring track were defined. Using the regression method, an analytical equation was modeled, combining the output capacity value of the sensor with the examined humidity changes. With the use of experimental results as well as the least square method, the values for the above equation’s parameters were determined. The knowledge of coverage factor characteristics for the convolution of four selected probability distributions was used for the research.

For the calibration of small flowrates and for use with different gases, a novel double piston prover with a spindle-stepper motor drive has been developed. The piston prover allows flowrates being generated with a very good reproducibility and flowrate constancy, and it therefore also makes possible the calibration of meters under test which generate a constant flowrate like critical nozzles. By means of this principle, it was possible to realize for the first time a flowrate comparator which can also be used for the measuring of gas flows.

In the hardness standard, the top of national traceability chain is the primary hardness blocks. The National Metrology Institute of Japan (NMIJ) will start calibration service of primary Brinell hardness blocks. The uncertainty of the Brinell blocks is considered following to the test conditions presented in the paper.

The evaluation of the electrical energy flows is at the base of all operations connected to the commercial transactions in energy market. The assessment of "metrological quality" of the power/energy measuring apparatuses is well establishes in ideal sinusoidal conditions. But, with increasing diffusion of power electronics the typical characteristics of power network are far from sinusoidal one. In this paper a new methodology for quality assurance of energy meters in non sinusoidal operating conditions is reported. The description of methodology and some experimental results obtained are discussed in detail.