The burden test of a current transformer (CT) is an essential test to ensure the accuracy of the CT's readings. In this article, we will discuss how to do the burden test of CT and analyze the test report to determine the CT parameters.
Firstly, we need a CT PT analyzer to perform the burden test of CT. This device is used to apply a load to the CT and measure the resulting current and voltage. Once we have the CT PT analyzer, we can proceed with the burden test.
To begin the test, we must connect the CT to the analyzer and set the analyzer to a specific burden value. The burden value should match the expected load that the CT will experience in normal operation. Once the analyzer is set, we can begin taking measurements.
During the test, the analyzer will apply the burden to the CT, and we can measure the resulting current and voltage. These values can then be used to calculate the power (P) consumed by the CT. The power consumption is then compared to the CT's rated burden to determine whether the CT is accurate within its specified range.
After performing the test, we will have an analysis test report that provides us with all the relevant parameters for the CT. Some of the parameters include ratio error, phase displacement, and relative error. The ratio error indicates the deviation from the expected ratio between the CT's secondary current and primary current. The phase displacement measures the angle between the CT's secondary current and primary current. Finally, the relative error is the accuracy of the CT's measurements at different loads.
In conclusion, the burden test of CT is a necessary step in ensuring the accuracy of CT readings. By using a CT PT analyzer, we can measure the CT's power consumption, which allows us to determine if it's within the specified range. The analysis test report provides us with information about the CT's parameters, allowing us to assess its accuracy and make any necessary adjustments.