Single- and 3-phase systems for heavy duty applications |
The
museum has a limited collection of plugs and sockets meant for single
and three-phase heavy duty applications. In residences three-phase
usually ends at the door step, but occasionally it is used for powering
electrical stoves, dryers or fans. More often you will find it at
farms, recreational areas as campings and marinas, and in
hospitals and workshops. The single phase devices are rated up to 250V-32A, or 125V-50A. Three-phase devices are restricted to models that are sold in hardware stores for do-it-yourself applications. Typical ratings are: 380-400V-10 to 32A and, in North America and Japan, 250V-15 to 50A, or 480V-15 to 30A. Devices for industrial applications, which usually exceed 400/480V, and power plants are beyond the scope of the museum. The classification of heavy duty and three-phase items is based on their origin. Select a category below for images and details. |
Three-phase
alternating current. A separate page on 3-phase generators explains the principle of three-phase alternating current. 110-125V, 208V, 220-250V, 277V, 380-400V and 480V. Worldwide, various voltages are used in mains power systems. 380, 400 and 480 Volt are typical for three-phase systems. A short introduction to the origin of these voltages is given on a separate page. |
D i g i t a l M u s e u m o f | P l u g s a n d S o c k e t s |