Columbia Motor installations ordinance (§ 27-104)
Chapter 27: Utilities · Article III. Water and Light System
In short: Electric motors over 10 horsepower must be three-phase unless the director gives special approval. A three-phase motor's starting current can't exceed 8 percent of the serving feeder's full load capacity, and motors starting without current-limiting starters max out at 25 horsepower on a 2,400-volt feeder and 150 on a 13,800-volt feeder.
Our plain-English summary, not the official text or legal advice. The ordinance below is what counts.
(a) Electric motors larger than ten (10) horsepower shall be three-phase, except by special approval of the director.
(b) The starting current for any three-phase motor shall not exceed eight (8) percent of the full load capacity for the department's distribution feeder which serves the motor. The maximum size motor which will be permitted to start across the line without current limiting starters for various feeder voltages, is as follows:
2,400 volt feeder ..... 25 horsepower
13,800 volt feeder ..... 150 horsepower
Official source: City of Columbia official Code of Ordinances (online): look up Sec. 27-104
Text from Supplement 139 (September 3, 2026).
Last checked November 1, 2026. The city's official copy controls; this page is a reading copy, not legal advice.