New York State Master Electrician Practice Exam

Where is MV (multi voltage) cable rated not allowed to be installed?

1. Underground trench

2. Raceway

3. Cable tray

4. Wall outlets

The correct answer is: Cable tray

The correct answer highlights a critical safety concern regarding the installation of MV (multi voltage) cables. MV cables are designed to operate at specific voltage levels, and their construction may not conform to the safety requirements necessary for certain environments, particularly those where there may be significant exposure to physical damage or where the cable might not be adequately protected. One crucial factor in determining where MV cables can be installed is the risk associated with their use in environments such as cable trays. In a cable tray system, cables are exposed and can be subject to various environmental factors, including mechanical stress, moisture, and temperature fluctuations. The open nature of a cable tray can expose MV cables to physical damage, which poses a higher risk of electrical failure or hazards. In contrast, other environments like underground trenches or raceways provide additional protection that can mitigate risks associated with exposure and physical damage, making them more suitable for MV cable installation. Additionally, wall outlets typically involve lower-voltage applications, which further distinguishes them from MV cable requirements. Understanding these specific safety parameters is essential for proper installation practices to prevent electrical hazards and ensure compliance with electrical codes and regulations.