Service-entrance conductors must have an ampacity greater than or equal to the rating of the service disconnect.

• A. Less than
• B. Less than or equal to
• C. Greater than
• D. Greater than or equal to

Answer: (D)

The main concept is sizing service-entrance conductors to match the service disconnect rating. The conductors must be able to carry at least the current the disconnect is rated to interrupt, so their ampacity must be greater than or equal to the disconnect’s rating. If the conductor’s ampacity were less, it could overheat under high load before the disconnect can clear the fault. The equal case is allowed, which is why “greater than or equal to” is the correct relationship. Choices that imply less-than or strictly greater-than fail to cover all valid scenarios, including when the ampacity exactly matches the disconnect rating.