HomeworkLib
Question

A 10 kVA transformer has 2 % resistance and a rated core loss of 150 watts....

A 10 kVA transformer has 2 % resistance and a rated core loss of 150 watts. At what percent of its rated kVA will this transformer operate to achieve maximum efficiency?

86.6 %

89.3 %

88.2 %

91.2 %

Two single-phase transformers with equal ratings and turns ratio are operated in parallel to supply a load of 180 kW at a lagging pf of 0.90. Transformer A has a resistance of 1% and a reactance of 6%. Transformer B has a resistance of 2% and a reactance of 5%. Calculate the power delivered by each transformer.

85 kW, 95 kW

90 kW, 90 kW

88 kW, 92 kW

80 kW, 100 kW

A 20:1 potential transformer is used with a 150-volt voltmeter. If the instrument deflection is 118 volts, calculate the line voltage.

5900 V

885 V

2360 V

None of these

engineering   Electrical-Engineering   
0 0
Add a comment Improve this question Transcribed image text
Next > < Previous
Sort answers by oldest

Homework Answers

Answer #1

0 0
Add a comment
Know the answer?
Add Answer to:
A 10 kVA transformer has 2 % resistance and a rated core loss of 150 watts....
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions

  • A 50-kVA, 13,800/208-V, Delta to Wye connected distribution transformer has an equivalent resistance of 3 percent...

    A 50-kVA, 13,800/208-V, Delta to Wye connected distribution transformer has an equivalent resistance of 3 percent and a reactance of 9 percent per unit. (a) what's the transformers phase impedance referred to the high side voltage? (b) what's the transformers voltage regulation at full load and 0.9 PF leading? equivalent resistance of 3 percent and a reactance of 9 percent per unit. (a) What is the transformer's phase impedance referred to the high-voltage side? (b) Calculate this transformer's voltage regulation...

  • A single-phase 10 kVA, 460/120 V, 60 Hz, transformer has an efficiency of 96% when it...

    A single-phase 10 kVA, 460/120 V, 60 Hz, transformer has an efficiency of 96% when it delivers 9 kW at 0.9 pf lagging. The transformer is connected as an autotransformer to supply load to a 460 V circuit from a 580 V source. Show the autotransformer connection Determine kVA rating of the autotransformer Determine the efficiency of the autotransformer at full-load with 0.9 pf lagging

  • 3. Three single-phase, 10 kVA, 460/120 V, 60 Hz transformers are connected to form a three-phase...

    3. Three single-phase, 10 kVA, 460/120 V, 60 Hz transformers are connected to form a three-phase 460/208 V transformer bank. The equivalent impedance of each transformer referred to HV side is 1.0 + j2.0 Ω. The transformer delivers 25 kW at 0.9 pf lagging at rated voltage. Answer the following questions: (a) Draw a schematic diagram showing the transformer connection. Draw three separate single-phase transformers and complete their primary and secondary connections. (b) Determine the magnitude of transformer primary and...

  • 4. [Transformer - 15 points) A 50-kVA, 13,800/208-V, A-Y distribution transformer has an equivalent resistance of...

    4. [Transformer - 15 points) A 50-kVA, 13,800/208-V, A-Y distribution transformer has an equivalent resistance of 3 percent and a reactance of 9 percent per unit. (a) What is the transformer's phase impedance referred to the high-voltage side? (b) Calculate this transformer's voltage regulation at full load and 0.9 PF leading.

  • Q6. A 50 Hz, 25 kVA 7200/240 V transformer has the following equivalent circuit parameters: Prima...

    Please show full working Q6. A 50 Hz, 25 kVA 7200/240 V transformer has the following equivalent circuit parameters: Primary resistance-1562, secondary resistance-0.02 Ω Primary leakage reactance-140Q, Secondary leakage reactance-0.15Q, Magnetising reactance 30 k2, Core loss resistance 200 k2 (a) The transformer is connected to two loads in parallel. The first load is 10 kW at 0.866 power factor lagging and the second load is 15kVA with a power factor of 0.8 lagging. Find the percentage regulation and power efficiency...

  • Q6. A 50 Hz, 25 kVA 7200/240 V transformer has the following equivalent circuit parameters: Prima...

    Help me answer c and d Q6. A 50 Hz, 25 kVA 7200/240 V transformer has the following equivalent circuit parameters: Primary resistance-1562, secondary resistance-0.02 Ω Primary leakage reactance-140Q, Secondary leakage reactance-0.15Q, Magnetising reactance 30 k2, Core loss resistance 200 k2 (a) The transformer is connected to two loads in parallel. The first load is 10 kW at 0.866 power factor lagging and the second load is 15kVA with a power factor of 0.8 lagging. Find the percentage regulation and...

  • A 1500-kVA, 6.6 kV, 50 Hz, 6-pole, three-phase, star-connected synchronous generator has a resistance 0.5Q/phase and a...

    A 1500-kVA, 6.6 kV, 50 Hz, 6-pole, three-phase, star-connected synchronous generator has a resistance 0.5Q/phase and a synchronous reactance of 5Q/phase. The generator is supplying its rated power at its rated voltage and at a power factor lagging. The rotational loss is 2 kW. Calculate: (a) the power developed, (b) the power angle, (c) the voltage regulation, and (d) the shaft torque. A 1500-kVA, 6.6 kV, 50 Hz, 6-pole, three-phase, star-connected synchronous generator has a resistance 0.50/phase and a synchronous...

  • 4. Figure shows a power source that feeds a 100 kVA 14/2.4 kV transformer through a...

    4. Figure shows a power source that feeds a 100 kVA 14/2.4 kV transformer through a feeder with impedance of 100/60° Ω Load 90 kw 0.85 PF lagging Feeder transmission line) Source Transformer Load The transformer has been tested to determine its equivalent circuit. The results of the tests are: Open-circuit test Voc = 14 kV oc 0.1 A Рос-800 w Short-circuit test Vsc 800 V Isc = 7A Psc 2 kW The load on the transformer is 90 kW...

  • A 5 KVA, 480/120V, 60 Hz, non-ideal transformer has the following primary and secondary resistance and...

    A 5 KVA, 480/120V, 60 Hz, non-ideal transformer has the following primary and secondary resistance and reactance values R 80,X1-12Q, R 0.15Q, X 0.20, R 18 KQ, and X 15 KO If the transformer is operating at 90% of its rated load current and the voltage is leading the current by 40 degree: a) Draw the approximate equivalent circuit of the transformer referred to secondary side, b) Calculate the efficiency of the transformer, and c) The voltage regulation

  • A 150 MVA, 22/220 KV transformer has p.u. resistance of 1.2% and reactance of3.5%.The magnetizing impedance...

    A 150 MVA, 22/220 KV transformer has p.u. resistance of 1.2% and reactance of3.5%.The magnetizing impedance is 136.6+ 185j p.u. The transformer supplies the rated current at 0.92 PF. Find the Equivalent circuit referred to the secondary. Find the Voltage regulation Find the copper losses and the core closes of the transformer. Find the efficiency of the transformer.

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT