Ratio testing of a transformer is performed to verify the correct turns ratio between the primary and secondary windings, ensuring the transformer delivers the expected voltage output. This test compares the actual ratio with the nameplate specifications to detect issues like winding short circuits, open circuits, or incorrect connections. It is typically carried out using a transformer turns ratio (TTR) tester. Accurate ratio testing is essential during manufacturing, commissioning, and maintenance to confirm performance and operational safety. Any deviation from the specified ratio can impact voltage regulation and overall system efficiency, making this a critical step in transformer quality assurance.
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