The main factors affecting the test results of the oil pressure tester are as follows:
1. Environmental impact
Dust and water vapor in the atmosphere inevitably immerse themselves in the oil sample to be tested, resulting in lower measurement values. Therefore, the standard includes a method of adding a dust cover to the oil cup and completing the measurement as soon as possible. If conditions permit, the measurement should be carried out in a clean and dry laboratory with air conditioning, especially in the humid and rainy season in the south and the season with heavy sand and dust in the north of China, to prevent environmental conditions from affecting the measurement results.
2. The influence of experimental instruments
The oil pressure tester includes a boosting device (manual or automatic), an oil cup and electrode, a stirring device (manual or automatic), a data output device (analog instrument or digital printer), a timing device, etc. Any abnormality in each part can cause errors in the measurement results. Automatic instruments are better and basically eliminate the influence of factors during the measurement process.
2.1 Oil Cup and Electrode
The shape of the electrodes is different, and the electric field in the space around the electrodes is also completely different. The electric field between flat chamfered electrodes can be roughly regarded as a uniform electric field, while the electric field between spherical and spherical cap electrodes is an uneven electric field. The performance of insulating oil in different electric fields is also almost different. The capacity of the oil cup and the depth of electrode immersion in insulating oil can all affect the measurement results, and there are clear regulations in relevant standards. Practice has shown that differences in electrode processing and assembly levels, as well as the shape and material of the oil cup, can lead to significant differences in the measurement results.
2.2 Boosting device
Whether the output voltage waveform of the boosting device is similar to a sine wave and whether the output voltage is consistent with the output display has a significant impact on the accuracy of the results. Different testing instruments must ensure that the performance of their boosting devices meets the standards. The performance of the boosting device should be guaranteed by the manufacturer in the design and production of the instrument. Users can request the output voltage spectrum analysis and output voltage peak detection report of the boosting device from the manufacturer when purchasing the instrument.