Figure 3. Three phase power has three identical sine waves overlapping at an offset of 2π/3 radians or 120°. When one phase reaches an x-intercept or node the next phase is only 30° and approximately 5.6 milliseconds from reaching its crest.
“NSF/ANSI 61.” NSF RSS. The Public Health and Safety Organization, n.d. Web. 07 June 2017.
Gorman-Rupp SF Series® Submersible Solids-handling Pump
Submersible Turbine Pumps
Utah Lake Cascade Pump
Vertical Lathe
National Pump Vertical Turbine Pumps, API 610
Horizontal Lathe
Impeller wear ring
Bowl wear ring
Schlumberger Pump Assembly
Figure 2. A simple sine wave with a period of 360° and an amplitude of 1. In single phase power the x-intercepts are 180° from each other. A full period is 360°. A single phase motor has a crest approximately every 16.5 milliseconds giving the motors a tendency to vibrate more, which may contribute to a shortened bearing life.
80 Series® Engine Driven
Parley’s Water Treatment Plant. Photo credit SLCdocs.com