3.4.14 C2 - Capacitance Match
The Interwinding capacitance match test calculates the ratio between two capacitance measurements on two groups of windings. It is measured by applying a specified ac voltage between two separate windings and the voltage across and current flow between the two windings is measured to obtain a complex impedance. This is performed to the two groups in turn.
This test is suitable for switched mode power supply, audio and telecommunication transformers. It checks that the windings are installed in the correct positions on the bobbin.
On selecting "C2 Interwinding Capacitance Match" from the available tests window, a dialogue box will be displayed.
To program the test:
- Enter the voltage and frequency required for the test.
(Refer to Chapter 7 - ‘Test Conditions’, which lists recommended test conditions for different values of capacitance.)
- Select the integration time you require.
'Medium' is the default setting. 'Long' will give more stable readings (for tighter limits) at the expense of an increased test time, and 'Short' will test at the maximum speed, but may give a slightly noisier reading.
- Select the terminals to be included for both high and low X test terminals.
- Selecting Terminals [Y] prompts a second dialogue box allowing the second set of windings to be configured for the test.
- Set the capacitance limits.
- Select OK. The test specification will then be displayed in the program window.