Why should the case of a high-voltage transformer be grounded?

• A. To protect personnel from shock
• B. To prevent high static voltages
• C. A and B
• D. None of the above

Answer: (C)

Grounding the case of a high-voltage transformer is essential for several safety and operational reasons. First and foremost, grounding protects personnel from electrical shock. If the transformer develops a fault that causes the casing to become energized, grounding ensures that any stray voltage is safely routed away to the earth, significantly reducing the risk of electrocution for anyone who might come into contact with the transformer.

In addition to personnel safety, grounding also plays a crucial role in preventing high static voltages. High-voltage transformers can generate static electricity that may accumulate on surfaces, potentially creating an electric discharge. By grounding the transformer casing, this static charge can be dissipated safely, thereby reducing the likelihood of unintended sparking or other electrical hazards.

Therefore, the correct choice encompasses both the protection of personnel and the prevention of dangerous static voltages, highlighting the importance of grounding in high-voltage environments.