NICET Electrical Power Testing 5

Question 1

In the fall-of-potential ground resistance test, the potential probe is typically placed at what percentage of the distance to the current probe?

Accepted Answer

62%

Answer

The 62% rule places the potential probe at 62% of the electrode-to-current-probe distance for accurate readings.

Question 2

Which standard covers electrical safety in the workplace, including arc flash requirements?

Accepted Answer

NFPA 70E

Answer

NFPA 70E is the Standard for Electrical Safety in the Workplace.

Question 3

Very low frequency (VLF) withstand testing of medium-voltage cables commonly uses a frequency of:

Accepted Answer

0.1 Hz

Answer

VLF testing typically uses 0.1 Hz to reduce the charging power needed for long cable lengths.

Question 4

Per NETA thermography guidelines, a temperature difference greater than 15°C between similar components under similar load indicates:

Accepted Answer

A major discrepancy requiring immediate repair

Answer

NETA classifies a >15°C rise between similar components as a major discrepancy requiring immediate repair.

Question 5

Under the NEC, a single ground rod with resistance above what value requires a supplemental electrode?

Accepted Answer

25 ohms

Answer

NEC 250.53(A)(2) requires a supplemental electrode unless a single rod is 25 ohms or less.

NICET - National Institute for Certification in Engineering Technologies Practice Test