Experiment No.: 5
Determine the regulation & efficiency of single-phase transformer by direct loading method.
- Regulation of single-phase transformer by direct loading method
- Efficiency of single-phase transformer by direct loading method
Although two chief difficulties which do not warrant the testing of large transformer by direct load test are:
- Large amount of energy has to be wasted in such a test.
- It is stupendous (impossible for large transformer) task to arrange a load large enough for direct loading. Yet this test can be performed to find out the efficiency & voltage regulation of small rating transformers.
Efficiency, η = Output Power / Input Power
% η =((P2) / (P1)) × 100
% Voltage regulation up= ((No load voltage – Full load voltage)/Full load voltage)×100
% Voltage regulation down= ((No load voltage – Full load voltage)/No load voltage)×100
|Sl. No.||Name of Apparatus||Quantity||Specification||Makers name|
|1.||Single phase wattmeter||2|| 0-750-1500-3000 W|
|2.||Single Phase Transformer||1||230/115 V|
|3.||Ammeter||1||0-5 A, MI type||KEW|
|4.||Ammeter||1||0-10 A, MI type||Sushama|
|5.||Voltmeter||1||0-300 V, MI type||Sushama|
|6.||Digital Multimeter||1||0-750 V AC, 0-1000 V DC,|
|7.||Rheostat||1||0-100 W, 1kW|
Remarks: This method is not applicable for large rated transformer as a large amount of energy has to be wasted in such a test. During this test we should cautious about the heat radiated by the resistive load.