Master Electrician Exam (NEC)Load CalculationsEasy
A commercial building has 40 general-purpose 15A, 120V duplex receptacles. What is the minimum calculated receptacle load for this building, according to NEC Article 220.14(I)?
- A18,000 VA
- B3,600 VA
- C10,000 VA
- D7,200 VA
Show answer & explanationAnswer & explanation
Correct answer: D. 7,200 VA
According to NEC Article 220.14(I), each single or duplex receptacle outlet is considered as 180 VA. For 40 receptacles, the total connected load is 40 receptacles * 180 VA/receptacle = 7200 VA. This is the minimum calculated load before applying any demand factors.
Why the other options are wrong
- A. Incorrect. This would be 100 receptacles at 180 VA, or an incorrect application of demand factors.
- B. Incorrect. This might be from calculating 20 receptacles at 180VA.
- C. Incorrect. This value is not derived from the NEC 180 VA rule.
Commercial Receptacle Load
The minimum VA assigned to each general-purpose receptacle outlet for load calculation purposes in commercial and industrial occupancies, as per NEC 220.14(I).
- Each single or duplex receptacle is considered 180 VA.
- This value is used before applying any demand factors from Table 220.42.
- Applies to general-use receptacles, not specific appliance outlets.
Memory trick: Every Commercial Plug is One-Eighty.