To conduct a polarity test using a CT/PT analyzer, follow these steps in detail:

1. Connect the Analyzer to the Transformer:

• Ensure that the CT/PT analyzer is properly connected to both the primary and secondary terminals of the transformer. Use the analyzer's provided cables and connect the primary side (P1, P2) and the secondary side (S1, S2). Ensure all connections are tight and secure to avoid incorrect readings.

2. Select the Polarity Test Function:

• On the CT/PT analyzer, select the specific polarity test mode. This function is available on most analyzers and is designed to test the direction of the current or voltage flow between the transformer windings.

3. Apply a Small Test Signal:

• The analyzer will inject a small voltage or current signal into the primary winding of the transformer. The instrument will simultaneously monitor the secondary winding for the corresponding output signal.

4. Phase Angle Measurement:

• The analyzer checks the phase relationship between the primary input and secondary output signals. If the secondary output is in-phase with the primary input, the polarity is correct. If the secondary signal is 180 degrees out of phase, the polarity is reversed.

5. Interpret Results:

• The analyzer will display a result indicating if the polarity is correct or reversed. If the result shows reversed polarity, it means that the connections between the primary and secondary windings are not correctly aligned, which can affect protection and metering systems.

6. Polarity Indicators:

• If available, some CT/PT analyzers provide graphical indicators that show the expected direction of current flow (usually marked with arrows). This is useful for visually confirming the polarity test.

7. Re-check Connections:

• In case of reversed polarity, re-check the connections at the CT/PT terminals (P1, P2, S1, S2) and repeat the test to confirm the results. Correct any mistakes in wiring before retesting.

8. Refer to Standards:

• For specific guidelines, refer to standards such as IEC 61869 and IEEE C57.13, which outline proper procedures for transformer testing, including polarity verification.

This detailed approach ensures that the polarity of the CT or PT is correct and that the system can operate efficiently without causing relay misoperation or metering errors.

Oct 26,2024