To assist U.S. manufacturers, exporters and individuals living or traveling abroad, these pages list the characteristics of electric current available and the type of attachment plugs used in most countries. These pages are based on a handbook published in 1998 by the U.S Department of Commerce. The tables indicate the type of current (alternating or direct current), number of phases, frequency (hertz), and voltage, as well as the stability of the frequency and the number of wires to a commercial or residential installation. This information pertains to domestic and commercial service only. It does not apply to special commercial installations involving relatively high voltage requirements or to industrial installations.
For most countries listed here, two nominal voltages are given. The lower voltages are used primarily for lighting and smaller appliances, while the higher voltages are used primarily for air conditioners, heating, and other large appliances. Travelers planning to use or ship appliances abroad should acquaint themselves with the characteristics of the electric supply available in the area in which the appliance is to be used. In some cases, a transformer may be used to correct the voltage. However, if the appliance requires exact timing or speed and if the frequency of the foreign electricity supply differs from the one the appliance was designed for, contact Visicomm for frequency converters. Some foreign hotels have circuits providing approximately 120 volts which allow guests to use electric shavers and other low-wattage U.S. appliances.
The information presented here was compiled over a period of months from a large number of sources. Consequently, there is some possibility of errors or omissions for which we cannot assume responsibility. In addition, this information should not be taken as final in the case of industrial or highly specialized commercial installations. It would be impossible for us to maintain complete data on every foreign industrial installation. For special equipment for commercial use or heavy equipment for industrial use, the current characteristics for the area of installation should be obtained from the end user.
The 1997 edition was prepared by the Trade Development unit in the International Trade Administration, U.S. Department of Commerce.
Type of current-a.c. indicates alternating cuffent; d.c. indicates direct
Frequency-Shown in number of hertz (cycles per second). Note that
even if voltages are similar, a 60-hertz U.S. clock or tape recorder will
not function properly on 50 hertz current.
Number of phases-1 and 3 are the conventional phases that may be
Nominal voltage-The term nominal voltage is used to denote the
reported voltage in use in the majority of residential and commercial
establishments in the country or city. Direct current nominal voltages are
110/220 and 120/240. The lower voltage is always 1/2 of the higher
voltage. On a direct current installation, the lower voltage requires two
wires while the higher voltage requires three wires.
Alternating current is normally distributed either through 3 phase
wye ("star") or delta ("triangle"), 4-wire secondary distribution systems.
In the wye or star distribution system the nominal voltage examples are
120/208, 127/220, 220/380, and 230/400. The higher voltage is 1.732
(the square root of 3) times the lower voltage. In a delta or triangle
system, 110/220 and 230/460 are examples of nominal voltages. The
higher voltage is always double the lower voltage. The higher voltage is
obtained by using 2 or 3 phase wires and the neutral wire while the lower
voltage is the voltage between the neutral wire and one phase wire. The
higher voltage may be single or 3 phase while the lower voltage is
always single phase and used primarily for lighting and for small appliances.
Type of attachment plug in use-Attachment plugs used throughout
the world come in various forms, dimensions and configurations too
numerous for this document. The basic and most commonly used types of plugs are listed by country.
Adapters may be purchased to change from the American plug type to other types.
Number of wires to the consumer-The number of wires which may
be used by the consumer is shown. Normally, a single phase, 220/380
volt system or 127/220 system will have two wires if only the lower
voltage is available (one phase wire and the neutral). It will have three
wires if both the higher and lower voltages are available (two phase
wires and the neutral) and where three phase motors will be used, four
wires will be available for the higher voltage (the three phase wires and
the neutral wire).
Frequency stability-"Yes" indicates that the frequency is stable and
that service interruptions are rare.
If you need assistance with electric power frequency conversion, or have questions concerning the content of these pages please contact Visicomm.
Common Plug Types
Characteristic Listings by Country -
A thru F, G thru M, N thru Z