## 3 Results
### Verification Measurement of the Flow Characteristics of the Transducer  
In the verification measurement of the flow characteristics of the hydrostatic transducers, we base ourselves on the data specified by the manufacturer. Figure 8 shows the flow characteristics of the transducers depending on the revolutions specified by the manufacturer. In the primary and secondary circuits of our hydraulic equipment, transducers with a geometric volume of V\({}_{\rm G}\) = 17 cm\({}^{3}\) were used. Figure 6: Schematic of the primary circuit of a laboratory test equipment with connection of an electro-hydraulic proportional pressure valve. Verification of the flow characteristics took 10 s at a sampling rate of 20 ms. The parameters were measured by the HMG 3010 measuring device, and flow, pressure, and temperature sensors by the HMG measuring device (Figure 2). The basic statistical evaluation of the verification of the flow characteristics of the transducers in the primary and secondary hydraulic circuit is shown in Tables 8 and 9 and the flow rates in Figures 9 and 10. Figure 8: Flow characteristics of the transducers QHD-17R determined by the manufacturer. Figure 7: Control system of proposed laboratory equipment in LabVIEW. The verification measurement of the primary circuit of the laboratory test device was carried out in order to verify the function of individual elements of the test device, sensors, and control circuit C. Based on the evaluation of the verification measurement, it can be concluded that the test device is suitable for testing hydrostatic transducers, hydraulic circuit elements and simultaneous testing of various hydraulic fluids. The flow rate of the transducer in the proposed laboratory equipment corresponded to the values of the transducer manufacturer. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Flow Rate Q** & **Average** & **Median** & **Mode** & **Minimum** & **Maximum** & **Distraction** & \
\begin{tabular}{c} **Standard** \\ **Deviation** \\ \end{tabular} &
\begin{tabular}{c} **Variation** \\ **Coefficient** \\ \end{tabular} \\ \hline Rotation speed & \(\overline{\chi}\) & Me & Mo & \(\chi_{\min}\) & \(\chi_{\max}\) & \(\sigma^{2}\) & \(\sigma\) & \(\mathrm{V_{k}}\) \\
500 & 7.6446 & 7.65 & 7.77 & 7.21 & 7.99 & 0.033 & 0.182 & 2.388 \\
750 & 11.753 & 11.77 & 11.74 & 11.27 & 12.26 & 0.043 & 0.207 & 1.766 \\
1000 & 16.032 & 16.03 & 16.21 & 15.25 & 16.84 & 0.093 & 0.305 & 1.903 \\
1250 & 20.080 & 20.08 & 20.06 & 19.41 & 20.88 & 0.088 & 0.297 & 1.480 \\
1500 & 24.098 & 24.10 & 24.02 & 23.36 & 24.93 & 0.106 & 0.326 & 1.354 \\
1750 & 28.192 & 28.19 & 28.25 & 27.43 & 28.96 & 0.108 & 0.328 & 1.166 \\
2000 & 32.323 & 32.32 & 32.34 & 31.60 & 33.03 & 0.100 & 0.317 & 0.981 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Basic statistical evaluation, verification of flow characteristics of transducers in the primary circuit. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Flow Rate Q** & **Average** & **Median** & **Mode** & **Minimum** & **Maximum** & **Distraction** & \
\begin{tabular}{c} **Standard** \\ **Deviation** \\ \end{tabular} &
\begin{tabular}{c} **Variation** \\ **Coefficient** \\ \end{tabular} \\ \hline Rotation speed & \(\overline{\chi}\) & Me & Mo & \(\chi_{\min}\) & \(\chi_{\max}\) & \(\sigma^{2}\) & \(\sigma\) & \(\mathrm{V_{k}}\) \\
500 & 7.52 & 7.51 & 7.53 & 7.44 & 7.60 & 0.0007 & 0.026 & 0.351 \\
750 & 11.71 & 11.71 & 11.68 & 11.57 & 11.80 & 0.001 & 0.030 & 0.263 \\
1000 & 15.94 & 15.91 & 15.94 & 15.65 & 16.20 & 0.0013 & 0.036 & 0.227 \\
1250 & 20.14 & 20.14 & 20.08 & 19.62 & 20.77 & 0.0591 & 0.243 & 1.207 \\
1500 & 24.40 & 24.39 & 24.28 & 23.77 & 24.92 & 0.0960 & 0.309 & 1.270 \\
1750 & 28.60 & 28.62 & 28.45 & 28.10 & 29.07 & 0.0733 & 0.270 & 0.946 \\
2000 & 32.76 & 32.76 & 32.81 & 32.32 & 33.16 & 0.05002 & 0.223 & 0.682 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Basic statistical evaluation, verification of flow characteristics of transducers in the secondary circuit.