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A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V?
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A 5 kVA, 400/80 V transformer has equivalent resistance refered to pri...
To find the voltmeter reading across the load terminals, we need to calculate the secondary voltage of the transformer.

1. Calculate the apparent power:
The apparent power (S) can be calculated using the formula S = V1 * I1, where V1 is the primary voltage and I1 is the primary current.
Given:
V1 = 400 V
I1 = 9.3 A
S = 400 V * 9.3 A = 3720 VA = 3.72 kVA

2. Calculate the power factor:
The power factor (PF) can be calculated using the formula PF = P1 / S, where P1 is the real power.
Given:
P1 = 3.2 kW = 3200 W
PF = 3200 W / 3720 VA = 0.8602

3. Calculate the apparent power on the secondary side:
The apparent power on the secondary side (S2) can be calculated using the formula S2 = S / (N1/N2), where N1 and N2 are the number of turns on the primary and secondary windings, respectively.
Given:
N1/N2 = V1/V2 = 400 V / 80 V = 5
S2 = S / (N1/N2) = 3.72 kVA / 5 = 0.744 kVA

4. Calculate the secondary current:
The secondary current (I2) can be calculated using the formula I2 = S2 / V2, where V2 is the secondary voltage.
Given:
S2 = 0.744 kVA
I2 = 0.744 kVA / V2

5. Calculate the equivalent impedance on the secondary side:
The equivalent impedance on the secondary side (Zeq(LV)) can be calculated using the formula Zeq(LV) = V2 / I2.
Given:
Zeq(LV) = V2 / I2 = (V2 * V2) / S2
Zeq(LV) = (V2 * V2) / 0.744 kVA

6. Calculate the equivalent impedance referred to the primary side:
The equivalent impedance referred to the primary side (Zeq(HV)) can be calculated using the formula Zeq(HV) = (N1/N2)^2 * Zeq(LV), where N1 and N2 are the number of turns on the primary and secondary windings, respectively.
Given:
Zeq(HV) = 1.76 Ω
Zeq(HV) = (5^2) * Zeq(LV) = 25 * Zeq(LV)

7. Calculate the secondary voltage:
The secondary voltage (V2) can be calculated using the formula V2 = sqrt((V1^2) - (I1^2 * Zeq(HV))).
Given:
V1 = 400 V
I1 = 9.3 A
Zeq(HV) = 1.76 Ω
V2 = sqrt((V1^2) - (I1^2 * Zeq(HV)))

8. Calculate the voltmeter reading:
The voltmeter reading is the same as the secondary voltage.
Given:
V2 = secondary voltage
Voltmeter Reading = V2

By calculating the above steps, we can find the voltmeter reading across the load
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A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V?
Question Description
A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V?.
Solutions for A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? in English & in Hindi are available as part of our courses for Electrical Engineering (EE). Download more important topics, notes, lectures and mock test series for Electrical Engineering (EE) Exam by signing up for free.
Here you can find the meaning of A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? defined & explained in the simplest way possible. Besides giving the explanation of A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V?, a detailed solution for A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? has been provided alongside types of A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? theory, EduRev gives you an ample number of questions to practice A 5 kVA, 400/80 V transformer has equivalent resistance refered to primary, Req(HV) = 1.76 Ω and equivalent reactance referred to primay, Xeq(HV) = 3.74 Ω. A lagging load is being supplied by it resulting in the following meter readings (meters are placed on the HV side): I1 = 9.3 A, V1 = 400 V, P1 = 3.2 kW For this condition calculate what a voltmeter would read if connected across the load terminals. Neglect the no-load current of the transformer. A. 72.94 V B. 73.67 V C. 62.62 V D. 86.67 V? tests, examples and also practice Electrical Engineering (EE) tests.
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