*Question G4C12:
Why must all metal enclosures of station equipment be grounded?*  

*Correct Answer is  D: It ensures that hazardous voltages cannot appear on the chassis*  

### AI Response: (may contain errors)  

Grounding metal enclosures of station equipment is crucial for safety and proper operation. Let's break down the correct answer and the other choices.

### Correct Answer: D
**It ensures that hazardous voltages cannot appear on the chassis.**

- **Explanation**: Grounding the metal enclosures provides a safe path for electrical faults. If a fault occurs, such as a short circuit, the grounding system directs the excess current away from the equipment and into the ground. This prevents the chassis from becoming energized, which could pose a shock hazard to users.

### Why the Other Choices are Incorrect:

- **A: It prevents a blown fuse in the event of an internal short circuit.**
  - **Explanation**: While grounding can help manage fault conditions, it does not prevent a blown fuse. A blown fuse is a protective measure that interrupts the circuit when excessive current flows. Grounding does not influence whether a fuse will blow; it simply provides a safe path for fault currents.

- **B: It prevents signal overload.**
  - **Explanation**: Grounding does not prevent signal overload. Signal overload occurs when the input to a device exceeds its maximum capacity, leading to distortion or damage. Grounding is primarily a safety measure and does not affect signal levels directly.

- **C: It ensures that the neutral wire is grounded.**
  - **Explanation**: While grounding the neutral wire is important in electrical systems, this statement does not directly relate to the grounding of metal enclosures. The grounding of equipment enclosures is focused on safety from electrical shock rather than the status of the neutral wire.

### Summary
Grounding metal enclosures is essential for safety, ensuring that hazardous voltages do not appear on the chassis. This protects users from electric shock and helps maintain the integrity of the equipment. Remember, grounding is about safety, not about preventing blown fuses or signal overloads.