ICC Residential Electrical Inspectors Practice Exam

What is the minimum branch circuit rating for ranges if their rating is 8.75 kVA or more?

1. 30 AMP

2. 40 AMP

3. 50 AMP

4. 60 AMP

The correct answer is: 40 AMP

For ranges with a rating of 8.75 kVA or more, the minimum branch circuit rating is defined by the National Electrical Code (NEC). Since 8.75 kVA translates to roughly 37.5 amps (using the formula kVA multiplied by 1,000 and then divided by the line voltage, typically 240 volts for residential ranges), this necessitates a branch circuit that can handle the load without tripping or overheating. A 40 AMP rating is appropriate in this scenario as it provides enough capacity to safely support the load of the range while also taking into account factors like voltage drop and potential start-up currents that might occur. The circuit must ensure sufficient power delivery while maintaining safety and compliance with the code. A 40 AMP circuit also aligns well with the common wire and breaker configurations typically used in residential installations for ranges. Higher ratings such as 50 AMP or 60 AMP are more than what would be necessary for a load of 8.75 kVA, which could lead to the installation of oversized wiring or equipment that doesn't optimize the electrical system's efficiency for the intended application. Hence, 40 AMP is both compliant and practical for ranges rated at 8.75 kVA or more.