Use Voltmeter, ammeter, wattmeter to determine active, reactive and apparent power consumed in given R-L series circuit, draw phasor diagram.

1 Answer

Answer :

Practical Significance

In the industry environment Electrical Engineering diploma graduate are expected to measure basic parameters like voltage, frequency, time period etc. for R—L series circuits. Therefore this practical will help you to acquire necessary AC series circuits skills.


Relevant Program Outcomes (POs)

Discipline knowledge: Apply Electrical engineering knowledge to solve broad based Electrical engineering related problems.

Experiments and practice: Plan to perform experiments and practices to use the results to solve broad-based Electrical engineering problems.

Engineering tools: Apply relevant Electrical engineering and tools with an understanding of the limitations.

Individual and team work: Function effectively as a leader and team member in diverse/ multidisciplinary teams.


Competency and Practical Skills

This practical is expected to develop the following skills for the industry identified competency ‘Maintain electrical systems applying AC and DC circuit fundamentals’:

i. Select relevant range of meters.

ii. Select suitable resistance and inductance.


Relevant Course Outcome(s)

l. Troubleshoot problems related to single phase A.C series circuits.


Practical Outcome

1. Use voltmeter, ammeter, wattmeter to determine active, reactive and apparent power consumed in given R-L series circuit. Draw phasor diagram.


Relevant Affective domain related Outcome(s)

1. Follow safety electrical rules for safe practices.


Minimum Theoretical Background

Impedance of RL circuit-Impedance of RL circuit is the phasor sum of resistance and inductive reactance and its unit is Ω.


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Phasor diagram of RL circuit:- It is the diagram show in phasor relationship between voltages VR, VL and V with respect to current I.


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AC power for series RL Circuit:- AC power is the phasor sum of active, reactive and apparent power as shown in power triangle diagram..

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Practical set-up / Circuit diagram / Work Situation

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Resources Required

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Precautions

1. Ensure proper earthing to the equipment.

2. Ensure the power switch is in ‘off’ condition initially.


Procedure

1. Connect the circuit as per circuit diagram.

2. Set the rheostat for maximum resistance.

3. Set the variac to zero output and switch on a.c. mains.

4. Apply a suitable voltage adjusting the variac, so that a suitable current flows.

5. Measure and note the voltages across R and L, current and power through it. Also measure the output of voltage of variac.

6. Repeat the above procedure for different output voltages of variac/varying R/varying L.

7. Draw the phasor diagram for each of reading for verification.

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