NEC Commercial Electrical Practice Test

For each dryer served, what is the minimum necessary wattage if the nameplate rating is lower?

1. 4000 watts

2. 4500 watts

3. 5000 watts

4. 5500 watts

The correct answer is: 5000 watts

The minimum necessary wattage for each dryer served, if the nameplate rating is lower, is established by the National Electrical Code (NEC) to ensure safe operation and adequate performance. In the NEC, specifically under Article 220, dryers are typically required to have a minimum demand of 5000 watts applied for calculation purposes, regardless of the actual nameplate rating. This requirement is in place to prevent undersizing the circuit and to account for potential variations in power usage that may occur in practice. It ensures that the electrical system can handle the maximum load a dryer may demand, thus protecting the equipment and reducing the risk of overloading the circuit. Other wattage choices, while significant, do not meet the NEC’s specified minimum. Adhering to the 5000-watt standard allows for safe and efficient operation of the dryer, ensuring that all potential electrical requirements are covered. This ensures compliance with code and enhances safety in residential or commercial installations.