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LOAD TEST ON SINGLE PHASE TRANSFORMER

51355420-LAB-MANUAL-FOR-E-E-CS.pdf (Size: 523.09 KB / Downloads: 94)

FORMULAE

1. Input Power =Wattmeter reading × Multiplication factor in Watts

Where,

Multiplication factor =

2.Output power = VSY × ISY × cosf in Watts.

Where VSY - Secondary Voltage in Volts.

ISY- Secondary current in Amps.

3.Percentage of Efficiency = × 100 %

4.Percentage of Regulation = × 100 %

Where, VO – No Load Voltage in Volts

VL – Load Voltage in Volts

PRECAUTION

• No Load Condition should be observed at the time of starting

• Meters are checked for proper Type and rating.

PROCEDURE

• Connections are given as per the circuit diagram.

• The SPST Switch on the Primary side is closed and the DPST Switch on the Secondary side is

opened.

• The Autotransformer is adjusted to Energize the transformer with rated Primary Voltage

• The Volt meters and Ammeters Readings are noted and tabulated at No load condition

• The DPST switch on the secondary side is closed.

• The transformer is loaded upto 130% of the Rated Load, corresponding Ammeters, Voltmeters

and Wattmeters readings are noted and tabulated.

• After the observation of all the readings the load is released gradually to its initial position.

• The Autotransformer is brought to its initial position

• The Supply is switched off.

GRAPH

The graph drawn as

• Output power Vs Efficiency

• Output power Vs Regulation