Question: In accordance with NETA and IEEE standards the correct maintenance test voltage (dc) for 5kV rated EPR 100% insulation level cable is?
14kV
11kV
9kV
5kV
18kV
According to Table 100.6.1, the answer is 28. perhaps i am missing something.
[Transformers]
1. A wye-delta transformer has a primary line voltage of 7200 V and a secondary voltage of 360 V. What is the turns ratio?
Your Answer: 20:1
Correct Answer: 11.55:1
Help: [What is the turns ratio?]
A 4160V circuit is equipped with 200/5 CTs, at full scale what should the panel ammeter read if the circuit was operating with a power factor of 0.8%?
Should the question provide primary side amps so I can convert to Panel readings using CT ratio?
7200/360 = 20
20/1.732 = 11.55 Turns ratio
Convert the vector (–1.0, 1.0) into magnitude/angle form.
Answers have -45, 0, 2, 45, and 135 degrees as potentials. -1,1 is in the third quadrant, meaning the angles should be between 180 and 270 degrees (in this case 215), vice the I believe 135 degree which is marked as the correct answer.
- Which of the following acceptance tests is optional for a 13200-480Y/277V 2500kVA dry-type transformer?
Your Answer: Power-factor or dissipation-factor tests on all windings
Help: NETA ATS-2021 7.2.1.2.B
Per NETA ATS-2025 7.2.1.2.B.3 Power-factor or dissipation factor tests on all windings is optional.
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11. Pressurizing a liquid-filled transformer tank with N2 will prevent the entrance of water.
Your Answer: True
Correct Answer: False
IEEE Std C57.140 (2006) guide for evaluation and reconditioning of liquid‑immersed power transformers:
“Positive nitrogen pressure (along with a good gasket) keeps oxygen and moisture out.”
