Chapter 6, Problem 1RQ

To determine

The minimum rating for a service entrance disconnecting means for a single family dwelling and the section in $NEC$ that states the rule.

Explanation of Solution

According to the National electric code the circuit conductors between the final overcurrent device and the power or lightning outlet is defined as a branch circuit.

According to the National electric code section $230.79\text{(C)}$ the service entrance disconnecting means for a single family dwelling shall have minimum rating of $100\text{amps}$ , $\text{3-wire}$ .

The minimum rating for a service entrance disconnecting means for a single family dwelling is $\text{100}\text{amps}$

Conclusion:

Thus, The minimum rating for a service entrance disconnecting means for a single family dwelling is $\text{100}\text{amps}$ and the section in $NEC$ that states the rule is $\text{230}\text{.79}\left(\text{C}\right)$ .