Based on the 2026 NEC.
Question: What are the standard voltages recognized by the NEC for load calculations?
See answer below.
Answer: 120, 120/240, 208Y/120, 240, 347, 416Y/240, 480Y/277, 480, 600Y/347, and 600 volts
Reference: Section 120.5(A)
Explanation: For the 2026 NEC, calculations were relocated to a new article 120. 416Y/120 was also added as a standard nominal voltage as it is becoming increasingly popular in industrial and commercial facilities.
Lupacchino is a senior design engineer with Gaylor Electric, Inc. in Noblesville, Ind. and serves as an alternate on NEC Code-Making Panel No. 3. He is currently licensed in more than 80 jurisdictions. He can be reached at [email protected]