Certified Energy Manager Practice Exam

What would be an indicator of poor quality of electrical power?

1. Voltage peaks in the frequency domain

2. Over-voltage and under-voltage conditions

3. Consistent phase alignment

4. Low total harmonic distortion

The correct answer is: Over-voltage and under-voltage conditions

Over-voltage and under-voltage conditions serve as clear indicators of poor quality in electrical power. These conditions can lead to various issues within electrical systems, including potential damage to equipment, operational inefficiencies, and increased energy consumption. When voltage levels exceed or fall short of the acceptable range, equipment can experience stress, overheating, or malfunctions, impacting the overall reliability and efficiency of power delivery. In a well-functioning system, voltage should remain within prescribed limits to ensure that devices operate effectively and that energy is utilized efficiently. Monitoring for over-voltage and under-voltage conditions helps identify problems in the power supply, allowing for timely interventions to maintain power quality and ensure operational integrity. Other options can represent different aspects of power quality but do not directly signify poor quality as clearly as over-voltage and under-voltage. For example, consistent phase alignment generally indicates stable power delivery, while low total harmonic distortion suggests that the power is largely free from interference and distortions. Voltage peaks in the frequency domain may indicate transient events or disturbances but do not by themselves define the overall quality of power in the same straightforward manner as fluctuations in voltage levels.