The correct answer is: D. 500 mega ohms
Insulation resistance is the resistance between two conductors that are insulated from each other. It is measured in megohms (MΩ). The insulation resistance of a high voltage circuit breaker must be high enough to prevent current from flowing between the live and neutral terminals when the breaker is open.
The insulation resistance of a high voltage circuit breaker is typically more than 500 mega ohms. This is because high voltage circuit breakers are designed to interrupt high currents. If the insulation resistance were too low, current would flow between the live and neutral terminals even when the breaker is open. This could cause a fire or other damage.
The insulation resistance of a high voltage circuit breaker is tested periodically to ensure that it is still within the required specifications. If the insulation resistance is too low, the breaker must be replaced.
Here is a brief explanation of each option:
- Option A: 1 mega ohms. This is the minimum insulation resistance required for some low voltage circuit breakers. However, it is not sufficient for high voltage circuit breakers.
- Option B: 10 mega ohms. This is the insulation resistance required for some medium voltage circuit breakers. However, it is not sufficient for high voltage circuit breakers.
- Option C: 100 mega ohms. This is the insulation resistance required for some high voltage circuit breakers. However, it is not the typical value.
- Option D: 500 mega ohms. This is the typical insulation resistance required for high voltage circuit breakers.