A breakdown voltage (BDV) tester for oil determines the dielectric strength of the oil sample by measuring the voltage at which electrical breakdown occurs within the sample.
Here's a step-by-step explanation of how the process works:
Sample Preparation:
The oil sample is carefully poured into the test chamber of the BDV tester, ensuring there are no air bubbles or contaminants.
The test chamber is typically designed with two electrodes separated by a fixed distance, creating a uniform electric field.
Voltage Application:
The BDV tester applies a steadily increasing voltage across the electrodes, starting from a low level.
The voltage is typically increased at a controlled rate, such as 2 kV/s or 3 kV/s, depending on the test standard.
Breakdown Detection:
As the voltage increases, the BDV tester continuously monitors the current flowing through the oil sample.
When the voltage reaches a level where the oil can no longer withstand the electric field, electrical breakdown occurs, oil bdv tester and a sudden increase in current is detected.
Breakdown Voltage Measurement:
The voltage at which the breakdown occurs is recorded as the breakdown voltage (BDV) of the oil sample.
This breakdown voltage is directly related to the dielectric strength of the oil, as it represents the maximum electric field the oil can withstand before experiencing electrical failure.
Calculation of Dielectric Strength:
The dielectric strength of the oil is typically calculated by dividing the breakdown voltage by the electrode gap distance.
The dielectric strength is usually expressed in units of kilovolts per millimeter (kV/mm) or volts per micrometer (V/μm).
The resulting dielectric strength value provides a quantitative measure of the oil's ability to resist electrical breakdown and serve as an insulating medium. This information is crucial for evaluating the quality and suitability of the oil for various electrical applications, such as transformers, switchgear, and other high-voltage equipment.
The BDV tester's accuracy and precision in measuring the breakdown voltage are essential for determining the oil's dielectric strength reliably and consistently.
