Museum of Plugs and Sockets logo, small Single- and 3-phase systems
for heavy duty applications
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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.


IEC 60309 info about standard
IEC 60309 plugs and sockets
NEMA 14-30P
North America
German obsolete 3-phase plug
Perilex and classic German
and Dutch types
Japanese 250V-20A twistLock plug
Belgian 16A 3-phase plug
Belgium New Zealand 32A plug
Australia and New Zealand
French 20A 3-phase plug
France (current models)

Classic French material
Swiss 16A 3phase plug
Spanish 16A-380V plug

Spain Italian 10A trifase plug, type Magic

Danish 16A 3-phase plug

Denmark Polish 25A-500V 3-phase socket

Poland, classic material
Norwegian 25A-230V plug

Czechoslovak 3-phase plug

Czech Republic
and Slovakia

IEC 62196
IEC 62196
plugs for electric vehicles

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.


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