GATE Exam  >  GATE Questions  >  Test results for a 30 kVA, 3000/1 10 V transf... Start Learning for Free
Test results for a 30 kVA, 3000/1 10 V transformer is given below:
OC test: 1500 V, 0.25 A, 87.5 W
SC test: 150 V, 10 A, 500 W
1. Estimate the percentage efficiency at full load and 0.8 pf
2. Estimate the percentage efficiency at half load and unity pf
3. Estimate the kVA output at which maximum efficiency occurs?
Most Upvoted Answer
Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC ...
**1. Estimating the Percentage Efficiency at Full Load and 0.8 Power Factor (pf)**

To estimate the percentage efficiency at full load and 0.8 power factor, we need to calculate the input power and the output power of the transformer.

Given:
- Rated power (kVA) = 30 kVA
- Rated primary voltage (Vp) = 3000 V
- Rated secondary voltage (Vs) = 10 V

**Step 1: Calculate the rated current (Ip) and rated secondary current (Is).**
Using the formula:
Ip = Rated power (kVA) / Rated primary voltage (Vp)
Is = Rated power (kVA) / Rated secondary voltage (Vs)

Ip = 30 kVA / 3000 V = 10 A
Is = 30 kVA / 10 V = 3000 A

**Step 2: Calculate the rated primary current (Ipr) and rated secondary current (Isr) at 0.8 power factor.**
Using the formula:
Ipr = Ip / Power factor (pf)
Isr = Is / Power factor (pf)

Ipr = 10 A / 0.8 = 12.5 A
Isr = 3000 A / 0.8 = 3750 A

**Step 3: Calculate the input power (Pin) and output power (Pout) at full load and 0.8 power factor.**
Using the formulas:
Pin = Vp * Ipr
Pout = Vs * Isr

Pin = 3000 V * 12.5 A = 37500 W
Pout = 10 V * 3750 A = 37500 W

**Step 4: Calculate the efficiency (η) at full load and 0.8 power factor.**
Using the formula:
η = (Pout / Pin) * 100

η = (37500 W / 37500 W) * 100 = 100%

Therefore, the estimated percentage efficiency at full load and 0.8 power factor is 100%.

**2. Estimating the Percentage Efficiency at Half Load and Unity Power Factor (pf)**

To estimate the percentage efficiency at half load and unity power factor, we need to calculate the input power and the output power of the transformer.

Given:
- Rated power (kVA) = 30 kVA
- Rated primary voltage (Vp) = 3000 V
- Rated secondary voltage (Vs) = 10 V

**Step 1: Calculate the rated current (Ip) and rated secondary current (Is).**
Using the formula:
Ip = Rated power (kVA) / Rated primary voltage (Vp)
Is = Rated power (kVA) / Rated secondary voltage (Vs)

Ip = 30 kVA / 3000 V = 10 A
Is = 30 kVA / 10 V = 3000 A

**Step 2: Calculate the rated primary current (Ipr) and rated secondary current (Isr) at half load and unity power factor.**
Using the formula:
Ipr = Ip / Power factor (pf)
Isr = Is / Power factor (pf)

Ipr = 10 A / 1 = 10 A
Isr = 3000 A / 1 = 3000 A

**Step 3
Explore Courses for GATE exam

Similar GATE Doubts

Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs?
Question Description
Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs?.
Solutions for Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? in English & in Hindi are available as part of our courses for GATE. Download more important topics, notes, lectures and mock test series for GATE Exam by signing up for free.
Here you can find the meaning of Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? defined & explained in the simplest way possible. Besides giving the explanation of Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs?, a detailed solution for Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? has been provided alongside types of Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? theory, EduRev gives you an ample number of questions to practice Test results for a 30 kVA, 3000/1 10 V transformer is given below: OC test: 1500 V, 0.25 A, 87.5 W SC test: 150 V, 10 A, 500 W 1. Estimate the percentage efficiency at full load and 0.8 pf2. Estimate the percentage efficiency at half load and unity pf3. Estimate the kVA output at which maximum efficiency occurs? tests, examples and also practice GATE tests.
Explore Courses for GATE exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev