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.”
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- Which IEEE trip curve would produce the shortest trip time given the relay information below?
Relay Pickup Current (A): 1000
Relay TD Setting: 1
Fault Current (A): 10000
Your Answer: IEEE Moderately Inverse
Correct Answer: IEEE Extremely Inverse
Help: Inverse Time Overcurrent Relays and Curves Explained
As shown in the link in the Help section, IEEE Extremely Inverse has the slowest trip time. Moderately Inverse should be the correct answer.
Testing motor circuits would best be achieved by use of Ohmmeter
Phase-angle meter
Ammeter
Megohmetter
Voltmeter
Testing in what way? These meters all have merit for different tests.
Which chapter of NFPA 70B specifically addresses personnel safety?
Your Answer: Chapter 4
Correct Answer: Chapter 5
new nfpa 70b 2023 is chapter 4 for safety
