List routine tests to be conducted on 3 phase transformer as per 1S-2026-2011.

List routine tests to be conducted on 3 phase transformer as per 1S-2026-2011. 
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Following tests are conducted/carried out on Transformer as per IS 2026 Routine tests of transformer include:-

1. Winding resistance measurement.(Both HV and LV winding ) 2. Measurement of insulation resistance.(Between HV and LV winding, HV and ground/tank, LV and ground/tank) 3. Measurement of voltage ratio/Turns ratio 4. Open circuit test (To determine no load loss, no load current /magnetizing current and shunt parameters of equivalent circuit) 5. Short circuit test (To determine full load losses, impedance voltage/short circuit impedance and series parameters of equivalent circuit.) 6. Polarity test 7. Phasing out test 8. Dielectric test of transformer or High Voltage Test. a. Power Frequency voltage with stand test or separate source voltage withstand test of transformer b. Induced voltage test of transformer. or DVDF (Double voltage double frequency) c. Impulse Voltage withstand test. 9. Vector group test. 10. Tests on on-load tap-changer, where appropriate. 11. To check against leakages through gaskets.

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