Answer / deepak24

1. SCT and OCT are performed to determine Copper and Iron Loss respectively. so by obtaining these values we can obtain efficiency as follows-
efficiency = input/(input+losses)
2. efficiency can be found for any desired load without connecting it to full load.
3. power consumption is less as compare to full load test.

Answer / binayak dey

In the open circuit test as the high internal resistance voltmeter is connected to the high voltage side and the low voltage side is loaded so the current flowing through the low voltage side is determined by the connected ammeter.so the copper loss is neglected and the power loss will also be neglected. So the power factor is minimise and hence the risk factor is minimum.

Answer / hassan

Open circuit test : Finding (Core losses) Rc & Xm.
,Finding Voltage with on load.

Short circuit test:Finding Equivalent (Resistance of windings & leakages flux) .

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