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SSC JE Electrical 2019 with solution SET-1
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In the two wattmeter method, the readings of the two wattmeters are 500W, 500W respectively. The load power factor in a balanced 3-phase 3-wire circuit is:

In two wattmeter method the phase angle is tanφ = √3(W1 − W2)/(W1 + W2) tanφ = √3(500 − 500)/(500 + 500) tanφ = 0° φ = tan−10° = 0° Power factor = cosφ PF = cos0° = 1

SSC JE Electrical 2019 with solution SET-1
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_______ is the measuring unit of inductive susceptance

Susceptance is symbolized by the capital letter B. It is the reciprocal of AC reactance. Susceptance, like reactance, can be either capacitive or inductive. In the case of a magnetic field, the susceptance is inductive. In the case of an electric field, the susceptance is capacitive. Capacitive susceptance is symbolized BC and inductive susceptance is symbolized BL. In the case of a magnetic field, the susceptance is inductive. In the case of an electric field, the susceptance is capacitive. Inductive susceptance is assigned negative imaginary number values, and capacitive susceptance is assigned positive imaginary number values.

The formula for inductive susceptance is

BL =–1/2πfL

The unit of Inductive susceptance is Siemen or Mho.

SSC JE Electrical 2019 with solution SET-1
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The meter constant of an energy meter will be given in:

Meter constant = No. of revolution/kWh

Hence the number of revolutions made by the disc for 1 kWh of energy consumption is called meter constant.

The meter constant is always written on the name plates of the energy meters installed m homes, commercial and industrial establishments. If the meter constant of an energy meter is 1500 rev/kWh, it means that for the consumption of 1 kWh, the disc will make 1500 revolutions.

SSC JE Electrical 2019 with solution SET-1
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What is the reason behind using a centrifugal switch in a single-phase induction motor?

The centrifugal switch is used to disconnect the starting winding of the motor once the motor approaches its normal operating speed i.e 50% – 70% speed.