Page 107 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

TASK 2 : Connecting and loading of transformer

1 After proper placing of transformers and fulfilling conditions as per step 1, perform the parallel connection of
transformers.
2 Make the connection of transformers as per the circuit diagram.

3 Switch ON the supply and record the primary and secondary voltages.
4 Apply the load step by step up to the full load current of transformers.
5 Note down the voltage and current readings and record in tabular column.
6 Verify that load current of both transformers are same, and load is shared by two transformers.
7 Switch OFF the supply and disconnect the circuit & transformers.

Tabular column

Primary Bus Primary Bus Secondary T/f -1 load T/f -2 load Total load
Voltage (VP) Current (IP) voltage (VS) current (I1) current (I2) current (IL)
400 V 230 V

Note: With above readings it is observed that, load current is equally shared by two transformers
Connected in parallel.
Safety precautions:
1 Do not make wrong and loose connections.
2 The conditions for parallel operation of transformer should be fulfilled

3 Do not load the transformers excessively.
4 Take the meters reading correctly.

90

CITS : Power - Electrician & Wireman - Exercise 44