## 2 Materials and Methods
To verify the functionality of the device, the conditions of the verification measurement were determined, where we tested a reference oil sample, an original oil filter, and an alternative oil filter in the reference measuring circuit A. In test circuit B, we applied contaminated oil, as well as the original and alternative oil filter. Contaminated engine oil with an oil filter was taken from the new Ivecco Crossway intercity bus, which had a mileage of 80,744 km. \begin{table}
\begin{tabular}{c c c} \hline \multicolumn{3}{c}{**Hydac Temperature Sensor ETS 4144-A-006-000**} \\ \hline
**Parameter** & **Unit** & **Value** \\ \hline Protection class acc. to DIN 43650 & IP & 65 \\ Supply voltage & V & \(8\div 32\) \\ Output signal, permitted load resistance & mA & \(4\div 20\) \\ Measuring range & \({}^{\circ}\)C & \(-25\div 100\) \\ Accuracy of measuring & \% & \(\leq\)\(\pm 0.4\) \\ Response time acc. to DIN EN 60751 & s & 4 \\ \hline \multicolumn{3}{c}{**Hydac flow sensor EVS 3104-A-0060-000**} \\ \hline Output signal, permitted load resistance & mA & \(4\div 20\) \\ Measured range (flow) & dm\({}^{3}\)/min & \(6\div 60\) \\ Measuring range (pressure) & MPa & \(40\) \\ Accuracy of measuring & \% & \(\leq\)2 \\ Supply voltage & V DC & \(10\div 32\) \\ Fluid temperature range & \({}^{\circ}\)C & \(-20\div 90\) \\ Operating temperature range & \({}^{\circ}\)C & \(-20\div 70\) \\ \hline \multicolumn{3}{c}{**Hydac pressure sensor HDA 4744-A-0250-000**} \\ \hline Protection class acc. to DIN 43650 & IP & 65 \\ Measuring range (pressure) & MPa & 25 \\ Accuracy of measuring & \% & \(\leq\)\(\pm 0.25\) \\ Supply voltage & V DC & \(12\div 30\) \\ Output signal, permitted load resistance & mA & \(4\div 20\) \\ \hline \end{tabular}
\end{table} 
Table 1: Basic data of flow, pressure, and temperature sensors [15]. Figure 1: Equipment for comparing the flow properties of oil filter materials in the lubrication circuits of internal combustion engines. Legend: A-reference measuring circuit, B-test measuring circuit, C-recording# and evaluation circuit. 1, 22-heaters; 2-tandem hydraulic pump; 3-coupling; 4-speed sensor; 5-frequency converter; 6-electric motor, 7, 23-tanks; 8, 24-safety valves; 10, 19, 26, 35-pressure sensors; 11, 18, 27, 34-flow sensors; 12, 21, 28, 37-temperature sensors; 13, 15, 29, 31-three-way valves; 14, 32-original filter materials; 16, 30-tested filter materials; 9, 17, 25, 33-sampling points; 20, 36-throttle valves; 38-computer with software; HG-tandem hydraulic pump; H\({}_{1}\), H\({}_{2}\)-heaters; N\({}_{1}\), N\({}_{2}\)-tanks; FM-frequency converter; SP-coupling; SO-speed sensor; PV\({}_{1}\), PV\({}_{2}\)-safety valves; Q\({}_{1.1}\), Q\({}_{1.2}\), Q\({}_{2.1}\), Q\({}_{2.2}\)-flow sensors; p\({}_{1.1}\), P\({}_{1.2}\), p\({}_{2.1}\), P\({}_{2.2}\)-pressure sensors; t\({}_{1.1}\), t\({}_{1.2}\), t\({}_{2.1}\), t\({}_{2.2}\)-temperature sensors; F\({}_{1.1}\), F\({}_{1.2}\), F\({}_{2.1}\), F\({}_{2.2}\)-filters in circuit A and B; TV\({}_{1.1}\), TV\({}_{1.2}\), TV\({}_{2.1}\), TV\({}_{2.2}\)-three-way valves; OV\({}_{1.1}\), OV\({}_{1.2}\), OV\({}_{2.1}\), OV\({}_{2.2}\)-sampling point; M-electric motor; SV\({}_{1}\), SV\({}_{2}\)-throttle valves. 3 comparison and evaluation of measured values of pressure and flow characteristics of oil filter MANN W950/26 and oil filter CNH Industrial 2992242;
4 the laboratory equipment measurement setting shall not change during the test, the hydraulic pump speed shall correspond to the nominal engine speed under operating conditions, and the speed value shall not change after adjustment \(\Delta n=\pm\) 1% or 10 rpm, whichever is greater.