Page 100 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

TASK 3: Connecting step down transformer and measure transformation ratio
1 Make the connection of step down transformer as per circuit diagram.
2 Check the connections and connect the transformer to the supply through the variac.
3 Switch ON the supply and record the primary & secondary voltages.
4 Switch OFF the supply and disconnect the transformer.
5 Calculate the transformation ratio of transformer.

Tabular column:
Transformer Primary Secondary voltage Transformer Remarks
Type Voltage (V1) (V2) ratio (K)

Step up If K ˃ 1 step up transformer
Step down If K ˂ 1 step down transformer
Isolation T/f If K = 1 Isolation transformer

Safety precautions:

1 Do not make wrong and loose connections.
2 Check & ensure the input supply voltage of transformer before connecting to supply.
3 Select proper range of voltmeters.

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CITS : Power - Electrician & Wireman - Exercise 41