You examine a test instrument commonly used to measure insulation resistance on equipment rated 600V or lower. The output of the test instrument is 1000 volts and the lead connections are? Your Answer: Positive, negative, guard
Correct Answer: None of the above
Help: Basic Test Equipment: Insulation Resistance Tester
Clicking on the provided link, I am taken to description of a megger stating that the terminals are positive, negative, and guard. I think this is meant to be a trick “gotcha” question, because there is a note saying that handheld meggers with outputs of 1000V or less might not have a guard terminal. There’s nothing in the question to imply that this is a handheld megger though.
*1. An electrical clearance of _____ shall be provided for commercial overhead service entrance conductors having a voltage rating of 480Y/277V that are not subject to truck traffic. Your Answer: 12 feet
Correct Answer: 12 feet
Help: NFPA 70-2017 Article 230.24(B)(2)
9. What is the main difference between sequential circuits and combinational circuits? Your Answer: Combinational circuits use logic gates, while sequential circuits use flip-flops.
Correct Answer: Combinational circuits have state or memory, while sequential circuits do not.
The reference provided to this question says the exact opposite in the very first paragraph.
3. You are asked to analyze a thermographic image of a single insulated electrical connection under 60% load, the ambient temperature recorded was 72°F and temperature points on the image indicate a temperature of 112°F at the connection in question, what would be the appropriate action level? Your Answer: Warrants investigation
Correct Answer: Monitor until corrected
Help: NETA Table 100.18
bit of a slant on this one I think… if they are calling the 50v cut off a “operating voltage”. Technically speaking, under 50v is considered dead right?
According to NFPA 70E, all employees shall be instructed to be alert at all times when they are working within the limited approach boundary of energized electrical conductors, regardless of the operating voltage.
Your Answer: True
Correct Answer: False
Help: NFPA 70E-2018 Section 130.6(A)(1)
NFPA 70E Article 130.6(A)(2)
Employees shall not be permitted to work within the limited approach boundary of energized electrical conductors or circuit parts operating at 50 volts or more, or where other electrical hazards exist, while their alertness is recognizably impaired due to illness, fatigue or other reasons.
NFPA 70, the National Electrical Code, requires Inspections and Tests on equipment over 1000V. Where is this in the code? Your Answer: 110.16
Correct Answer: 225.56
Help: Inspections and Tests
The correct code reference is 110.41. as the entirety of 110 part 3 is for installations over 1000v. Section 225 doesn’t have a .56
NFPA 70 2023
110.41 Inspections and Tests.
(A) Pre-energization and Operating Tests.
Where required elsewhere in this Code, the complete electrical system design, including settings for protective, switching, and control circuits, shall be prepared in advance and made available on request to the authority having jurisdiction and shall be tested when first installed on-site.
(B) Test Report.
A test report covering the results of the tests required in [110.41(A)] shall be available to the authority having jurisdiction prior to energization and made available to those authorized to install, operate, test, and maintain the system.
The question is: “Which sub-section of NFPA 70E requires that employer’s electrical safe work program include a policy on establishing an electrically safe work condition?”
Transformers 36. What are the two main components of the insulation in oil-paper insulated power transformers, and what is the role of each component? Your Answer: Oil provides mechanical stability, while cellulose improves the breakdown strength of the insulation.
Correct Answer: Cellulose provides mechanical stability, while oil acts as a conductor for the electrical currents.
Help: Moisture in Transformer Insulation
Oil acts as a conductor for electric currents??? Oil is the insulator.
