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From Wikipedia, the free encyclopedia

This article includes a list of countries and territories, with the plugs, voltages and frequencies they use for providing electrical power to small appliances and some major appliances. For definitions of terms and further information on each plug, see the article AC power plugs and sockets. For a discussion of the different voltages and frequencies used and some of the history of the different power systems see Mains electricity.


Wall sockets


The lettering system used here is from a U.S. government document[1], which defines the letter names and gives a (not always correct) list of what plug types are used where. Although useful for quick reference, the document is ambiguous in some areas. A plug and socket that are classified here under the same letter will usually mate, but there is no guarantee of this. A more up-to-date and authoritative reference on plugs and sockets is IEC Technical Report 60083[2].

Voltage ranges

Voltage and frequency:     220-240V/60Hz      220-240V/50Hz      100-127V/60Hz      100-127V/50Hz

Distinction should be made between the voltage at the point of supply (nominal system voltage) and the voltage rating of the equipment (utilization voltage). Typically the utilization voltage is 3 to 5% lower than the nominal system voltage; for example, a nominal 208 V supply system will be connected to motors with "200 V" on their nameplates. This allows for the voltage drop between equipment and supply. Voltages in this article are the nominal single-phase supply voltages and equipment used on these systems will carry slightly lower nameplate voltages. Three-phase and industrial loads will have other voltages. All voltages are root mean square voltage, the peak AC voltage is greater by a factor of \sqrt{2}, and the peak to peak voltage greater by a factor of 2 * \sqrt{2}.

Table of mains voltages and frequencies

Note: The table can be sorted alphabetically or numerically using the Sort none.gif icon.

Region Type(s) of plug / socket Voltage Frequency Comments
Afghanistan C, D, F 240 V 50 Hz Voltage may vary from 160 to 280.
Albania C, F 220 V 50 Hz
Algeria C, F 230 V 50 Hz
American Samoa A, B, F, I 120 V 60 Hz
Andorra C, F 230 V 50 Hz
Angola C 220 V 50 Hz
Anguilla A, B 110 V 60 Hz
Antigua A, B 230 V 60 Hz Airport power is reportedly 110 V.
Argentina C, I 220 V 50 Hz Live and neutral are reversed for socket outlet type I in comparison to most other countries.
Armenia C, F 230 V 50 Hz
Aruba A, B, F 127 V 60 Hz Lago Colony 115 V.
Australia I 230 V 50 Hz As of 2000, the mains supply voltage specified in AS 60038 is 230 V with a tolerance of +10% -6%[3]. This was done for voltage harmonisation - however 240 V is within tolerance and is commonly found. Mains voltage is still popularly referred to as being "two-forty volts". Bathrooms in hotels will often have a type I, C and A socket marked "for shavers only" as pictured on the right.
Austria C, F 230 V 50 Hz
Azerbaijan C 220 V 50 Hz
Azores C, F 220 V 50 Hz
Bahamas A, B 120 V 60 Hz along with 50 Hz in some outlying areas
Bahrain G 230 V 50 Hz Awali 110 V, 60 Hz.
Balearic Islands C, F 220 V 50 Hz
Bangladesh A, C, D, G, K 220 V 50 Hz
Barbados A, B 115 V 50 Hz
Belarus C 220 V 50 Hz
Belgium C, E 230 V 50 Hz
Belize A, B, G 110 V
220 V
60 Hz
Benin C, E 220 V 50 Hz
Bermuda A, B 120 V 60 Hz
Bhutan D, F, G, M 230 V 50 Hz
Bolivia A, C 220 V 50 Hz La Paz & Viacha 115 V.
Bonaire 127 V 50 Hz Receptacle is combination of B&C without ground connector.
Bosnia C, F 220 V 50 Hz
Botswana D, G, M 230 V 50 Hz
Brazil A, B, C, I - Older C, NBR14136:2002 / IEC 60906-1 - Newer devices 127 V
220 V
60 Hz Type I is becoming common for 220 V outlets and appliances in 127 V areas. Dual-voltage wiring is rather common for high-powered appliances, such as clothes dryers and electric showers which tend to be 220 V even in 127 V areas. Depending on the area, the exact voltage might be 115 V, 127 V, or 220 V. The A, B and C types are sometimes together (flat with rounder ends and ground pin) so that an A, B or C types can be used. Also note that by Jan 01st 2010, Brazil converted to the IEC 60906-1 international plug which looks similar to type J but is not compatible. Since then, all devices shall comply with new standard.
Brunei G 240 V 50 Hz
Bulgaria C, F 230 V 50 Hz
Burkina Faso C, E 220 V 50 Hz
Burundi C, E 220 V 50 Hz
Cambodia A, C, G 230 V 50 Hz
Cameroon C, E 220 V 50 Hz
Canada A, B 120 V 60 Hz Standardized at 120 V. 240 V single phase used for applications such as clothes driers, air conditioning, electric heating, wather heater, cook-stoves and machinery. Buildings and houses with more than one branch circuit have both voltages. Three-phase 120/208 V or 347/600 V is used many buildings. Type A outlets are for repairs only (house from the 1950s or older), type B now required for new construction and renovation. A 20-Amp type B but with a T-slot is used in kitchens in new construction. [4]
Canary Islands C, E, F, L 220 V 50 Hz
Cape Verde C, F 220 V 50 Hz
Cayman Islands A, B 120 V 60 Hz
Central African Republic C, E 220 V 50 Hz
Chad D, E, F 220 V 50 Hz
Channel Islands C, G 230 V 50 Hz
Chile C, L 220 V 50 Hz
China (mainland only) A, C, I 220 V 50 Hz Most wall outlets simultaneously support Types A and I. Some outlets support both Type A and Type C (the holes in the outlets are flat in the middle and round on the sides) so that either a Type A or a Type C plug can be used. The Type I outlet is next to the Type A & C outlet. Type A outlets only fit plugs with pins of the same width—a polarized Type A plug requires an adapter. NOTE: no matter the type of plug the socket will accept, voltage in china is always 220 volts. See photo at right.
Colombia A, B 120 V 60 Hz High-power air conditioners, restaurant equipment, cookstoves and ovens use 240 volt supplies. Wiring conventions, practices and standards follow the Colombian Electrical Code (Codigo Electrico Colombiano) which is essentially a translation of the USA National Electric Code.
Comoros C, E 220 V 50 Hz
Congo-Brazzaville C, E 230 V 50 Hz
Congo-Kinshasa C, D 220 V 50 Hz
Cook Islands I 240 V 50 Hz
Costa Rica A, B 120 V 60 Hz
Côte d'Ivoire C, E 230 V 50 Hz
Croatia C, F 230 V 50 Hz 3-phase 400 V AC used for heavy duty applications.
Cuba A, B 110 V 60 Hz
Cyprus G 240 V 50 Hz
Czech Republic C, E 230 V 50 Hz Type C Plugs are common, especially for low-power devices. Type C wall sockets are very uncommon, and exist only in very old installations.
Denmark C, E, K 230 V 50 Hz Type E is added from July 2008.[5]
Djibouti C, E 220 V 50 Hz
Dominica D, G 230 V 50 Hz
Dominican Republic A, B 110 V 60 Hz
East Timor C, E, F, I 220 V 50 Hz
Ecuador A, B 120 V 60 Hz
Egypt C 220 V 50 Hz
El Salvador A, B 115 V 60 Hz
Equatorial Guinea C, E 220 V 50 Hz
Eritrea C 230 V 50 Hz
Estonia C, F 230 V 50 Hz
Ethiopia C, E, F, L 220 V 50 Hz
Faroe Islands C, K 220 V 50 Hz
Falkland Islands G 240 V 50 Hz
Fiji I 240 V 50 Hz
Finland C, F 230 V 50 Hz
France C, E 230 V (formerly 220v) 50 Hz Type C wall sockets have been prohibited in new installations for more than 10 years.
French Guiana C, D, E 220 V 50 Hz
Gaza Strip C, H 230 V 50 Hz (see Israel in this list)
Gabon C 220 V 50 Hz
Gambia G 230 V 50 Hz
Georgia C 220 V 50 Hz
Germany C, F 230 V (formerly 220v) 50 Hz Type F ("Schuko", short for "Schutzkontakt") is standard. Type C Plugs are common, especially for low-power devices. Type C wall sockets are very uncommon, and exist only in very old installations.
Ghana D, G 230 V 50 Hz
Gibraltar G, K 240 V 50 Hz Type K was used in the Europort development by the Danish builders. Otherwise the United Kingdom fittings are used.
Greece C, F, (older)"Tripoliko" similar to type J and post-1989 type H 230 V (formerly 220v) 50 Hz Type F ("Schuko", Greek: Σούκο) is the de-facto standard for new installations' sockets. Type C sockets exist only in old installations. Light appliances use type C plug while more electricity-consuming ones use type E&F or F plugs.
Greenland C, K 220 V 50 Hz
Grenada G 230 V 50 Hz
Guadeloupe C, D, E 230 V 50 Hz
Guam A, B 110 V 60 Hz
Guatemala A, B 120 V 60 Hz
Guinea C, F, K 220 V 50 Hz
Guinea-Bissau C 220 V 50 Hz
Guyana A, B, D, G 240 V 60 Hz Mixture of 50 Hz and 60 Hz distribution according to Guyana Power and Light [6] Conversion of 50 Hz distribution to 60 Hz is ongoing [7]
Haiti A, B 110 V 60 Hz
Honduras A, B 110 V 60 Hz
Hong Kong G is used in almost all products, while M is (rarely) used when required current rating is between 13~15A. D is now obsolete in Hong Kong. 220 V 50 Hz Largely based on UK system. Occasionally, a 'shaver' socket (similar to Type C) is found in some bathrooms that provides low current to some other plug types. These almost always have a 110 V socket and a 220 V socket in the same unit, or a switch to select voltage, which are sometimes labelled as 110 V and 220 V. This duo installation is not as common in HK as in the UK. There was a smaller 2A version of type D, now obsolete.
Hungary C, F 230 V (formerly 220V) 50 Hz
Iceland C, F 230 V 50 Hz
India C, D, M 230 V 50 Hz The standardised voltage used in India is 220V/50 Hz with a tolerance varying from 216V to 253V. Some hotels provide dual receptacles for foreign appliances giving both 120V and 230V.
Indonesia C, F, G 127 V
230 V
50 Hz Type G socket/plug is less common.
Iran C, F 220 V 50 Hz Type C wall sockets are less common, and exist only in older installations. Type F is used for new installations. Type C Plugs are common for low-power devices.
Iraq C, D, G 230 V 50 Hz
Ireland G (obsolete or specialist installations may be D and M (as in the UK) or F) 230 V (formerly 220 V) 50 Hz G Sockets and plugs standard as defined by NSAI I.S. 401 (Plug) I.S. 411 (Socket outlet). Type F ("Side Earth") plugs occasionally seen in old installations probably because much of the early Irish electrical network was heavily influenced by Siemens. ' A 'shaver' socket (similar to Type C) is sometimes found in bathrooms that will provide low current to some other plug types. These almost always have a 110 V socket and a 230 V socket in the same unit, or a switch to select voltage, which are sometimes labelled as 115 V and 230 V. The G type socket often has a on-off switch on the socket. 110 V centre point earthed transformers are often used for industrial portable tools.
Isle of Man C, G 240 V 50 Hz
Israel C, H, M 230 V 50 Hz The standard for H plugs and sockets was recently modified to use round pins, so most modern sockets accept both type C and type H plugs. Type M sockets are used for air conditioners. Identical plugs and sockets also used in the Palestinian National Authority areas.
Italy C, F, L 230 V (formerly 220v)[8] 50 Hz
Jamaica A, B 110 V and 220V 50 Hz
Japan A, B 100 V 50 Hz
60 Hz
Eastern Japan 50 Hz (Tokyo, Kawasaki, Sapporo, Yokohama, and Sendai); Western Japan 60 Hz (Okinawa, Osaka, Kyoto, Kobe, Nagoya, Hiroshima). Older buildings have nonpolarized sockets, in which case American polarized plugs (one prong wider than the other) would not fit. Many buildings do not have the ground pin. Sockets and switches fit in American-sized standard boxes.
Jordan B, C, D, F, G, J 230 V 50 Hz
Kazakhstan C, E, F 220 V 50 Hz No official standard. Voltage tolerance is 220 V ±10%. Actual voltage may vary (usually 150-200 V) because of unstable electrical system.
Kenya G 240 V 50 Hz
Kiribati I 240 V 50 Hz
Kuwait C, G 240 V 50 Hz
Kyrgyzstan C 220 V 50 Hz
Laos A, B, C, E, F 230 V 50 Hz
Latvia C, F 220 V 50 Hz
Lebanon A, B, C, D, G 240 V 50 Hz
Lesotho M 220 V 50 Hz
Liberia A, B, C, E, F 120 V
240 V
50 Hz Previously 60 Hz, now officially 50 Hz. Many private power plants are still 60 Hz. A & B are used for 110v; C & F are used for 230/240v. Much of the centralized power system was destroyed during the civil wars starting in 1990, and public power supplies are still limited. Local supplies may vary and may not match the usual voltage for a particular wall socket. [9]
Libya D, L 127 V 50 Hz Barce, Benghazi, Derna, Sebha & Tobruk 230 V.
Lithuania C, F 230 V (formerly 220v) 50 Hz
Liechtenstein C, J 230 V 50 Hz Swiss Norm, C only in the form CEE 7/16.
Luxembourg C, F 230 V (formerly 220v) 50 Hz
Macau S.A.R. of China D, M, G, a small number of F 220 V 50 Hz No official standards there. However, in the Macao-HK Ferry Pier built by Portuguese Government before handover the standard was E & F. After handover, Macau adopted G in both government and private buildings. Before 1980s, 110V was found in Macau but now obsolete.
Macedonia C, F 220 V 50 Hz
Madagascar C, D, E, J, K 127 V
220 V
50 Hz
Madeira C, F 220 V 50 Hz
Malawi G 230 V 50 Hz
Malaysia G (but M for air conditioners and clothes dryers) 240 V 50 Hz The official mains power voltage is AC 230 V with the tolerance of +10%,-6%.[10] However, the supplied voltage remains at 240 V (except Penang at 230 V), as the supplied voltage is within the allowed tolerance. Type C plugs are very common with audio/video equipment. Plugged into Type G outlets using widely-available adapters or forced in by pushing down the shutter. The latter is widely practised, although hazardous.
Maldives A, D, G, J, K, L 230 V 50 Hz
Mali C, E 220 V 50 Hz
Malta G 230 V 50 Hz
Martinique C, D, E 220 V 50 Hz
Mauritania C 220 V 50 Hz
Mauritius C, G 230 V 50 Hz
Mexico A, B 127 V 60 Hz Type B is becoming more common. Voltage can legally vary by +/- 10% (giving a range of 114 to 140 volts). Split phase is commonly available and local electricians are apt to wire both to a type A/B socket to give 240 V for air conditioning or washing machine/dryers.
Micronesia A, B 120 V 60 Hz
Moldova C, F 220-230 V 50 Hz Compatible with European and former Soviet Union (GOST) standards.
Monaco C, D, E, F 127 V
220 V
50 Hz
Mongolia C, E 230 V 50 Hz
Montenegro C, F 220 V 50 Hz
Montserrat (Leeward Is.) A, B 230 V 60 Hz
Morocco C, E 127 V
220 V
50 Hz Conversion to 220 V only underway.
Mozambique C, F, M 220 V 50 Hz Type M found especially near the border with South Africa, including in the capital, Maputo.
Myanmar/Burma C, D, F, G 230 V 50 Hz Type G found primarily in better hotels. Also, many major hotels chains are said to have outlets that will take Type I plugs and perhaps other types.
Namibia D, M 220 V 50 Hz
Nauru I 240 V 50 Hz
Nepal C, D, M 230 V 50 Hz
Netherlands C, F 230 V (formerly 220v) 50 Hz
Netherlands Antilles A, B, F 127 V
220 V
50 Hz St. Martin 120 V, 60 Hz; Saba & St. Eustatius 110 V, 60 Hz, A, maybe B
New Caledonia E 220 V 50 Hz
New Zealand I 230 V 50 Hz Electricity Regulations 1997 states supply voltage is 230 V ±6%
Nicaragua A, B 120 V 60 Hz
Niger A, B, C, D, E, F 220 V 50 Hz
Nigeria D, G 240 V 50 Hz
North Korea C 220 V 50 Hz
Norway C, F 230 V 50 Hz

IT earthing system (most widespread)
TN earthing system (new installations)
TT earthing system (used in some installations in Bergen)

Okinawa A, B 100 V 60 Hz Military facilities 120 V.
Oman C, G 240 V 50 Hz Voltage variations common.
Pakistan C, D, M, G 230 V 50 Hz Official standard is 230 V / 50 Hz. Voltage tolerance is 230 V ±5% (218 V to 242 V). Frequency tolerance 50 Hz ±2% (49 Hz to 51 Hz) But Karachi Electric Supply Corporation (KESC) is 240 V / 50 Hz.
Type C and D Plug / Socket are common for low-power devices. Type M Plug / Socket is common for air conditioners and high-power devices. Type G Plug / Socket is less common.
Panama A, B 110 V 60 Hz Panama City 120 V.
Papua New Guinea I 240 V 50 Hz
Paraguay C 220 V 50 Hz
Peru A, B, C 220 V 60 Hz Talara 110/220 V; Arequipa 50 Hz
Philippines A, B, C 220 V 60 Hz Most plugs and outlets are Type A, but some are C. Type B are commonly found in high powered appliances and computers. Sockets and switches are built to USA dimensions and fit USA sized wall boxes. Some areas have 110V as in Baguio.
Poland C, E 230 V (formerly 220v) 50 Hz Type C Plugs are common, especially for low-power devices. Type C Soviet sockets could be seen in old houses and in countryside. Industrial appliances use 3-phase 400V AC (formerly 380V AC) supply.
Portugal C, F 220 V[11] 50 Hz
Puerto Rico A, B 120 V 60 Hz
Qatar D, G 240 V 50 Hz
Réunion E 220 V 50 Hz
Romania C, F 230 V (formerly 220v) 50 Hz Virtually identical to German standards. Most household sockets still compatible with East European standards (4.0 mm pins). Industrial appliances (washing machines, welding equipment) use 3-phase 400V AC supply.
Russian Federation C, F 220 V 50 Hz USSR (along with much of Eastern Europe) used type GOST sockets with 4.0 mm pins instead of the 4.8mm standard used by West European type C/E/F Plugs. The former Soviet sockets could be seen mainly in old houses and in countryside. Obsolete standard 127 V/50 Hz AC is used in some remote villages. Elsewhere it was replaced in 1970s by the 220V standard. Industrial appliances use 3-phase 380V AC supply.
Rwanda C, J 230 V 50 Hz
St. Kitts and Nevis A, B, D, G 110 V
230 V
60 Hz Region plug is same as United States (2 pin) 110-120 V
St. Lucia (Winward Is.) G 240 V 50 Hz
St. Vincent (Winward Is.) A, C, E, G, I, K 230 V 50 Hz
São Tomé and Príncipe C, F 220 V 50 Hz
Saudi Arabia A, B, F, G 127 V
220 V
60 Hz
Senegal C, D, E, K 230 V 50 Hz
Serbia C, F 220 V 50 Hz
Seychelles G 240 V 50 Hz
Sierra Leone D, G 230 V 50 Hz
Singapore G (but M for air conditioners and clothes dryers) 230 V 50 Hz Type C is used for audio/video equipment and plug adapters are widely available.
Slovakia C, E 230 V 50 Hz
Slovenia C, F 230 V 50 Hz 3-phase 400 V AC used for heavy duty applications.
Somalia C 220 V 50 Hz
South Africa M 220 V 50 Hz Grahamstown & Port Elizabeth 250 V; also found in King Williams Town
South Korea A, B, C, F (Types A & B are used for 110-volt installations and/or found in very old buildings. Types C & F are used for 220 Volts.) 220 V 60 Hz Type F is normally found in offices, airports, hotels and homes. Type C (type CEE 7/17) sockets are obsolete as of 2008 but still found in a lot of places. In cases where a Type C socket was replaced with a Type F, the ground contact is often not connected to anything. 220 volt power is distributed by using both "live" poles of a 110 volt system (neutral is not used). 110 V/60 Hz power with plugs A & B were previously used but has already been phased out. Some residents install their own step-down transformers and dedicated circuits, so that they can use 110 V appliances imported from Japan or North America. Most hotels only have 220 V outlets, but some hotels offer both 110 V (Type A or B) and 220 V (Type C or F) outlets. Switches and outlets fit American-sized boxes.
Spain C, F 230 V (formerly 220v) 50 Hz
Sri Lanka D, M, G 230 V 50 Hz Increased use of type G in new houses/establishments. Mainly in Colombo and high end hotels.
Sudan C, D 230 V 50 Hz
Suriname C, F 127 V 60 Hz
Swaziland M 230 V 50 Hz
Sweden C, F 230 V 50 Hz Sockets lacking earth is prohibited in new installations.
Switzerland C, J 230 V 50 Hz C only in the form CEE 7/16.
Syria C, E, L 220 V 50 Hz
Tahiti A, B, E 110 V
220 V
60 Hz/50 Hz Marquesas Islands 50 Hz [12]
Taiwan A, B 110 V 60 Hz Most outlets are Type A. When an outlet is Type B, the ground (earth) holes are usually not connected to anything in older houses. However, in modern houses you'll find them to be properly grounded. Most appliances have Type A plugs, but some appliances have Type B plugs. The ground prong on the Type B plus is often cut off to make it fit in Type A sockets in older buildings. Sockets and switches are built to USA dimensions and fit USA sized wall boxes. Dedicated sockets provide 220V for air conditioning units.
Tajikistan C, I 220 V 50 Hz
Tanzania D, G 230 V 50 Hz
Thailand A, B, C, F 220 V 50 Hz Outlets in hotels and newer buildings are usually a combination of types B and C which will accept plug types A, B and C while outlets in older buildings are usually type A. An equal proportion of appliances have type A or C plugs, or B if an Earth connection is required. Type F is mainly for high-powered appliances such as air conditioners, kettles and cookers. A 3-pin plug that only fits in B/C sockets is also seeing increased use, it differs from type B by having all the pins round. [13]
Togo C 220 V 50 Hz Lome 127 V.
Tonga I 240 V 50 Hz
Trinidad & Tobago A, B 115 V 60 Hz
Tunisia C, E 230 V 50 Hz
Turkey C, F 230 V 50 Hz
Turkmenistan B, F 220 V 50 Hz
Uganda G 240 V 50 Hz
Ukraine C, F 220 V 50 Hz
United Arab Emirates C, D, G 220 V 50 Hz
United Kingdom G (D and M seen in very old installs and specialist applications) 230 V (formerly 240 V) 50 Hz Voltage tolerance of 230 V +10%/−6% (216.2 V to 253 V), widened to 230 V ±10% (207 V to 253 V) in 2008. The system supply voltage remains centered on 240 V. [14] A "shaver socket" (similar to Type C) is sometimes found in bathrooms that will provide low current to some other plug types. These sometimes have a ~110 V socket and a ~240 V socket in the same unit, or a switch to select voltage for a single socket. The G type socket usually has an on-off switch. IEC 60309 plugs and connectors are used in industrial and construction locations as well as for outdoor use in domestic and other business premises. Plug types D and M were used until the 1960s and are still in preferred use for theatre and TV stage lighting applications due to lack of internal fuse.
United States of America A, B 120 V 60 Hz Standardized at 120 V. Electricity suppliers aim to keep most customers supplied between 114 and 126 V most of the time. 240 V/60 Hz used for heavy duty applications such as air conditioners, clothes dryers, stoves, ovens, and water heaters. Buildings with more than two branch circuits will have both 120 and 240 V available. Since 1962, Type B outlets are required by code in new construction and renovation. A T-slot Type B is rated for 20 amperes for use in kitchens or other areas using large 120 V appliances.
Uruguay C, F, I, L 230 V (formerly 220 V) 50 Hz Type F becoming more common as a result of computer use. Neutral and live wires are reversed, as in Argentina.
Uzbekistan C, I 220 V 50 Hz
Vanuatu I 230 V 50 Hz
Venezuela A, B 120 V 60 Hz Type G found in household 220V service only for air conditioning and some high power appliances.
Vietnam A, C 220 V 50 Hz Type A is the norm in Southern Vietnam and Type C is the norm in Northern Vietnam (according to the pre-unification border at 17 degrees North). Type G is found only in some new luxury hotels, primarily those built by Singaporean and Hong Kong developers. But Type G is never found in homes, shops, or offices.
Virgin Islands A, B 110 V 60 Hz
Western Samoa I 230 V 50 Hz
Yemen A, D, G 230 V 50 Hz
Zambia C, D, G 230 V 50 Hz
Zimbabwe D, G 220 V 50 Hz
A (NEMA 1-15 USA 2 pin)
B (NEMA 5-15 USA 3 pin)
C (CEE 7/16)
C (CEE 7/17 Euro 2 pin)
D (BS546 5 A version of Type M )
E (French)
F (CEE 7/4 "Schuko")
E+F (CEE 7/7)
G (BS1363 Fused 13 A, 5 A and 3A also in common use)
H (SI 32 Israel)
I (AS-3112 Argentina / Australia / New Zealand)
I, plus sockets for A, C and I (China)
J (SEV-1011 Switzerland)
K (SRAF 1962/DB Denmark)
L (CEI 23-16 Chile / Italy)
M (15 A version of Type D BS546)


  1. ^ Electric current abroad
  2. ^ IEC/TR 60083: Plugs and socket-outlets for domestic and similar general use standardized in member countries of IEC. International Electrotechnical Commission, May 2004. This 359-page technical report describes all national standards for domestic plugs and sockets. Its 1963 predecessor, CEE Publication 7, covered only the plugs and sockets of continental Europe.
  3. ^ AS60038-2000 Standards Australia - Standard Voltages
  4. ^ Rick Gilmour et al., editor, Canadian Electrical Code Part I, Twentieth Edition, C22.1-06 Safety Standard for Electrical Installations, Canadian Standards Association, Toronto, Ontario Canada (2002) ISBN 1-55436-023-4, diagram 1 and rule 26-700
  5. ^ Danish Safety Technology Authority (Sikkerhedsstyrelsen)
  6. ^ History of Guyana Power and Light, retrieved 2009 July 31
  7. ^ GPL Converting Parts of the City to 60 Hz, retrieved 2009 July 31
  8. ^ Enel
  9. ^ "History". Liberia Electricity Corporation. Retrieved 2008-10-26. 
  10. ^ Guidelines For Electrical Wiring In Residential Buildings - Energy Commission of Malaysia.
  11. ^ Ministérios da Indústria e Energia e do Equipamento Social - Decreto Regulamentar n.º 90/84
  12. ^ Electricity around the world
  13. ^
  14. ^ Lighting Industry Federation Ltd (2001) LIF Technical Statement No. 15,European Voltage Harmonisation. Accessed 2008-08-20

See also

External links


Travel guide

Up to date as of January 14, 2010

From Wikitravel

Universal Plug Adaptor
Universal Plug Adaptor

This article is a travel topic.

Electrical systems differ around the world. Some use 110-120 volts and others 220-240 volts. Some use 50 hertz and others 60 hertz. The plugs are also different and often incompatible. However, travelers with electrical appliances can take a few steps to ensure that they can be used at their destination.

Map of the world coloured by voltage and frequency
Map of the world coloured by voltage and frequency

Start by taking a look at the back of the device you want to use. If it says "100-240V, 50/60 Hz" or a greater range, it will work anywhere in the world, and you can skip right to the next section. If it doesn't, keep reading.

Dealing with electricity differences can be daunting, but it actually isn't too hard. There are only two main type of electric systems used around the world, with varying physical connections:

  • 110-120 volt, at 60 hertz frequency (in general: North and Central Americas, Western Japan)
  • 220-240 volt, at 50 hertz frequency (in general: the rest of the world, with some exceptions)

Occasionally, you will find 110-120 volts @ 50 Hz such as in Tokyo, Japan; and conversely, 220-240 volts @ 60 Hz such as in the Philippines and some parts of Brazil. Such systems are not common worldwide, though.

If the voltage and frequency for your device is the same as where you are travelling, then you need only worry about the physical plug. (The small difference between 110V and 120V is within the tolerances of most electrical devices. Likewise for 220V and 240V.)

If the voltage for your device is not the same, then you will need a transformer or converter to convert the voltage.

Giving a device a lower voltage than it was designed for is generally not dangerous; the device may not work correctly, but no dramatic failure is likely. Giving any device a voltage higher than it was designed for is dangerous, and will very likely damage the device. If you put 230 volts into a device designed for 110 it may melt, catch fire, or even explode.

Plug types
Plug types
Map of the world coloured by type of plug used
Map of the world coloured by type of plug used

A device that lets you insert a plug into a different socket is an adapter: these are small, cheap and safe. For example, between England and Germany, you need only an adapter. You stick your British plug in the adapter, which connects the rectangular phase and neutral prongs to the round German ones and puts the ground where the German outlet expects it, and you're good to go.

Unfortunately, there are many different plugs in the world. The three most widespread standards are:

  • The "American" (Type A) plug, with two vertical pins
  • The "European" (Type C) plug, with two round pins
  • The "British" (Type G) plug, with three rectangular pins

If your device has one of these plugs and you can adapt it to the others, you've got 90% of the world covered. (The main exceptions are South Africa, Australia, New Zealand, Argentina and parts of China, which use a Type I plug with two slanted pins.) Adapters between Type A and Type C and from C to G are tiny and cheap; converting Type A into G or Type G into anything else, on the other hand, needs a bulkier model.

For hobbyists: if you can't find an adapter, and you're staying for a longer time, just buy a separate plug at your destination, remove the existing plug and attach the new one. Unlike adapters, plugs are always available, and they're generally cheaper too. Caution: only try this if you know what you're doing! (Fire and/or electrocution are possible if inexperienced.)

As a last resort, a Type C plug can be forced into a Type G socket without any converter at all if you ignore what your mother told you and stick a pen or similar pointy object into the center (ground) hole, which fools the socket into thinking a ground pin has been inserted and opens up the other holes. Disable power to the socket and try to use something non-conductive to do this! Forcing a type C plug into a type G socket will damage the socket and will probably get you into trouble with the owner of the socket.

There's one more complication to consider: any two-pin socket is ungrounded, while all three-pin plugs are grounded. Trying to get grounding to work makes life more difficult, as any of sockets C, D, E, F, H, J, K or L will happily accept the ungrounded plug C, but will not work with any grounded variant other than their own. It's thus very tempting to use an adapter to turn a three-pin into a two-pin, but this will disable grounding, potentially leaving you vulnerable to electrocution and other electrical nastiness.

A last word of warning: many developing countries use multi-plug sockets that accept (say) both Type A and Type C. Don't assume the voltage is correct just because the plug fits, since a Thai Type A+C socket still carries 220V and may destroy American (110V) Type A devices.

Technical details

The difference between a transformer and converter is the way they deal with the wave-form of the electricity. Converters simply chop the wave in half. This is relatively simple and can be done in a small amount of space, so converters are comparatively light-weight and inexpensive. Transformers alter the length of the wave. This is more complicated and takes up more space: transformers are basically chunks of iron specially-wrapped in wires. So they are larger, heavier and more expensive. Electric appliances can function with either a full or half-sine wave, whereas electronic devices must have a full sine wave.

If you are using a 220V-240V appliance at 110V you will need a transformer.

If you are using a 110V appliance at 220V-240V you can also use a transformer, but may be able to get away with a (cheaper) converter.

If your device is an electric appliance with a heating element or mechanical motor such as a an iron or hair-dryer, then you can probably just use a converter. If your device is electronic, using electronic chips or circuits, such as a computer, printer, TV, microwave, VCR or even a battery charger, you will need a transformer.


  • They have two different types: "step-up" and "step-down". Step-up transformers allow you to plug a higher-voltage device into a lower-voltage power socket (e.g., using a UK device in the US.). Step-down transformers allow you to plug a lower-voltage device into a higher-voltage socket (e.g., using a US device in the UK.). Some transformers offer both. Take care to use the right type: if you plugged a 110-to-220 V step-up transformer into a 220 V socket you would get 440 V and a fried device.
  • You must also make sure that the power rating ("wattage") of your transformer is at least 10% greater than that of the device - otherwise the transformer can overheat and even catch fire. Before buying a transformer, look for the "input" figure - usually on the device's plug or in the manual. Some don't display wattage, but you can work it out simply by multiplying the voltage (V) and the current (amps (A); if mA, divide by 1,000). The resulting figure is the same as the wattage.
  • Transformers can be used with both electronic devices (e.g., those with chips and circuits) or electrical appliances (e.g., those with heating elements and motors). They can usually operate for a much longer time than converters.


These lighter-weight, less expensive devices can handle large wattage loads of up to 1600 watts, but they only step-down voltage, not raise it. They are suitable for those in 110-120V countries traveling to where the voltage is 220-240V. Converters are designed to operate for only an hour or two at a time, not continuously. As stated above, they cannot be used with electronic devices: devices that use chips or circuits, such as a computers, printers, VCRs or even battery chargers. A converter is normally given to a appliance that converts AC to DC.

Frequency (Hz)

Frequency is generally not a problem - most travel items will work on either 50 or 60 Hz. If all the electrical appliance does is produce heat or light, then the frequency is unlikely to matter.

Frequency is most likely to affect clocks and devices with motors. They may run faster or slower than they should and may be damaged in the long run as a result. Again, though, some motorised devices may function correctly on either 50 or 60 Hz - especially if they also operate on batteries. Just look on the label or plug.

However, you still may need to be careful if you have a sensitive or expensive device that converts AC (power from the wall) into DC (battery-like current) - especially if you also need to convert the voltage. A device will convert AC to DC to either : 1) save battery power by allowing you to plug into the mains or 2) to charge a battery in the device. The design of power supplies where AC is converted into DC does take frequency into account. Even though 60 Hz converts a little more easily to DC than 50 Hz does, there's enough tolerance in most small appliances and electronic gadgets that you can ignore frequency. However, if you also need to change the voltage (because the voltage of your device is different from the mains power voltage), you cannot use a switching-type converter. You must use the heavier iron-core transformer. If in doubt, consult a reputable electrical goods dealer.

If your device won't operate with a different frequency (powerful motors and non-quartz clocks), there is really nothing you can do to change it. Unlike voltage, frequency cannot easily be converted. Foreign embassies may have to use huge generators to provide current compatible with equipment from home.

If you desperately need to have power at your home country's frequency, you might try using a 12 volt DC to AC converter intended for vehicle use. However, most of these (especially those commonly found in stores) output a "sawtooth" wave instead of a sine wave. (Check the manufacturer's website if you need a sine wave output. It may be special order.) Make sure the wattage of the converter is sufficient for whatever device you need to operate, and the 12V battery has enough amps for the job. For example, 12V times 15 amps gives 180 watts (or less after losses are included).

Japan is a special case. East Japan (eg Tokyo) uses 50 Hz and west Japan (eg Osaka) uses 60 Hz. Equipment made for the Japanese market may have a switch to select 50 Hz or 60 Hz.

Unstable supply

In many developing countries, electrical supply is highly erratic and you need to take precautions to protect your equipment.

The main danger is power spikes, where the amount of power supplied temporarily surges to dangerous levels, with potentially catastrophic consequences. In developed countries, the main source of spikes is lightning strikes, but in developing countries they're most often associated with power outages since when the power comes back on, it rarely does so smoothly. The cheapest method of protection is thus simply to disconnect electronic devices as soon as the power goes out, and wait a few minutes after the power comes back on until plugging them back in.

Surge protectors are devices designed specially to protect against spikes and surges, and some are available in portable travel-sized versions. Some surge protectors can also be fitted to a telephone line to protect your phone or laptop modem. The most common variety use a metal oxide varistor (MOV), which shorts to ground if a given voltage is exceeded. These are easily destroyed by larger spikes, and better models will have a light indicating when the MOV has broken down, but you still need to keep an eye on them as the device will still continue to give power even if the protection is gone. There are also surge protectors with fuses, which are fail-safe (a blown fuse will stop power) and replaceable, but there still is a risk of a short, sharp spike which can pass through and damage your device before the fuse blows.

In some (mostly poor) regions, you may experience electricity voltage drops. Instead of 240V for example, you may only get 200V or even less (50% of the nominal supply voltage is not unknown). This happens especially if you're at "the end of the line" (far from the source or transformer) and is caused by the resistance of the electric lines themselves. Some appliances, such as light bulbs and heating equipment just keep working under a lower voltage, although a 20% voltage drop will cause a 36% power drop. Most electronic devices also keep working, but voltage drops are critical for fluorescent lamps and refrigerators, which may stop working altogether (usually without being damaged, when the voltage returns to normal, they will start working again).

Voltage drops can be solved with a special device called a voltage stabiliser. A stabiliser will raise the voltage again to its normal level. The principle is the same as for switching converters, except that stabilisers will produce a stable output, even with an unstable input. Stabilisers come in different power ranges, but they're all large, bulky and not practical to carry around. Be aware that some appliances, such as refrigerators, briefly consume twice or 3 times more power at start-up; the stabiliser should be able to provide this power. Voltage stabilisers can introduce surges if there is a power outage. The cheaper relay type can also damage electronic equipment.


If you are buying new appliances, get in the habit of checking the voltage. A dual-voltage hair straightener will cost you no more than a single voltage one, and save considerable hassle when travelling.

Laptop computers

Virtually all laptop computers (including those with internal power supplies) will handle a range of 100 to 240 volts and a frequency of 50 to 60Hz fine. In other words, you might not need a converter/transformer; most power supplies have supported ranges printed directly on them (like on this image), so have a look. However, you will definitely need to make sure that you have the plug that matches the outlet for the country you are going to.

If you are taking a laptop, you can use it to charge other items using a USB port on the laptop, even if they are normally not connected to it - this can save you a bundle of transformers in your luggage.


Radios also tend to be interchangeable from country to country. The exact FM range being used can vary from country to country though, so you may not be able to access all stations. In the US, only odd channels (88.1,88.3, 100.1 etc) are used. A radio intended for the US market will not work correctly in most other countries. Japan, in particular, has an FM band from 76 MHz to 90 MHz rather than the more common 87.5 MHz to 108 MHz. The countries of the former Soviet Union also use a similar band. For the medium wave band, channel spacings (the difference between each valid frequency) can be 9kHz or 10kHz (for USA). Some digital radios will have a switch or setting to choose which channel spacing is used. Without this, they will not work correctly outside their intended market. Old-fashioned analog-dial tuners don't have this limitation.

Mobile phones and digital cameras

Chargers for these may work with both 110V and 240V systems, though you may still need an adaptor plug or have to use the shaver socket. You may be able to get a second charger for the other voltage system, or even a dual voltage charger designed for both systems. However, your mobile phone handset may not be compatible with the country's network, or you may be limited to certain cellular providers. (See Telephone service for travel#Cell phones.)

Equipment using standard batteries

Battery sizes and voltages tend to be standard from place to place, and equipment that uses off-the-shelf batteries tends to be interchangeable. It may be difficult to get good quality batteries in some countries, especially alkaline batteries which are needed my most electronic equipment. If a cheaper battery is used, make sure to remove it as soon as it is exhausted or if the equipment will not be used for a while (risk of leakage).

Be cautious with:


In many countries without fully developed electrical power distribution systems, the use of generators is common. Generator supplies can be very good, however, in many places they are not, and can cause damage to sensitive equipment if it is connected. The voltage, frequency, and waveform shape (it should be a smooth sine-wave) can vary. In some places, people modify generators to run faster. This gives more voltage and power but increases the frequency too. The part of a generator that keeps it running at a constant speed is called the governor. If this is tampered with, the output voltage could rise sufficiently to cause damage. The best advice is not to connect valuable equipment to the supply, or at the very least disconnect it as soon as it is finished with.

If you are unsure about the quality of generator in use, there are a few simple rules. If it runs from petrol/gasoline it is bad - anyone serious about using generator power uses a diesel oil powered system. A good quality generator will have a low engine speed. 1500RPM for 50Hz or 1800RPM for 60Hz. If the engine speed is 3000RPM+, it is not a good machine.


Lamps and their light bulbs are very sensitive to voltage. If you shift between voltage systems, you will need to change the light bulbs to match the voltage, unless the lamp is designed to operate on both systems, say through a low voltage adaptor. If you buy a lamp abroad, you may need to have an electrician completely rewire a lamp when you get home to comply with your country's electrical safety standards. This may not be a problem for a one-off special item, but if you are going into the importing business it could be a showstopper.

Also watch out for the light bulb connection. In 110-120V systems this is often a screw connector while in 220-240V systems it is often a bayonet connector. These connectors also come in at least two different sizes. Be sure you can obtain light bulbs of the right voltage, size, and connector shape in the country you intend to use the lamp, and at a reasonable price, otherwise the lamp may become little more than junk when the bulb fails.

Electric motors

The electric motors in things like refrigerators, vacuum cleaners, washing machines and other whiteware are often sensitive to frequency. Older hairdryers and electric shavers might be also. Even if you use a step-up or step-down transformer, the different supply frequencies mean motors run at the wrong speed and burn out. The larger and more powerful the motor is, the more this is true. Don't, for example, bring a vacuum cleaner from the USA to Europe (or vice versa). It's almost guaranteed to fail -- even if you have a voltage converter.

Electric shavers

Hotels often provide a special electrical outlet specifically for electric shavers. They allow any voltage shaver to be plugged into them and be used safely in front of the bathroom mirror. They may also accept your cellphone adaptor or similar low power battery charging unit. Many – but not all – electric shavers sold today are dual voltage 50/60Hz and some will even recharge the battery at 12V DC (such as in an automobile). Check the label and instructions for compatibility.


Hairdryers are a particular risk; if you accidentally plug your 100-120 Volt hairdryer into a 240 Volt outlet you may find it catching fire in your hands! Similarly a 220-240 Volt hairdryer in a 120 Volt outlet may run slowly and not heat up enough. Most good hotels and motels will be able to supply a hair drier, it may even be a room fitting. However it may be worthwhile buying or borrowing a hairdryer suited for the electrical system of countries you may be travelling in.

Many new hairdryers sold in 100-120V countries are dual voltage with settings for 100-120V and 220-240V. Even though it's motorized, it will work on either 50 or 60 Hz. Be sure to "lock out" the high setting when it's plugged into 220-240 volts, or it will quickly burn out, or worse! (The low setting will be as powerful as the high setting was at 120V, with low speed unavailable.)


An electric clock of any sort is sensitive to voltage. If the voltage if doubled or halved it will not function and may burn out. Furthermore, the electric frequency (50 or 60 Hz) is used in cheap clocks - such as many clock radio style clocks - to keep the time. If the clock has a quartz crystal it uses this for the timekeeping and operates independently of the line frequency. Thus, if a clock made for North America were used in Europe – even with a voltage adapter – it would lose 10 minutes per hour! Obviously, not a great idea if you have a train to catch.

Video equipment

Televisions, many radios, video and DVD players, as well as videotapes, are often specific to the broadcast system used in the country that they are sold in, usually associated with the frequency of the country's electric current. For example, North America is 60 Hz and its television is 30 frames per second, while Europe is 50 Hz and its television is 25 frames per second. The main three television broadcast systems are PAL, the closest to a worldwide standard, NTSC, used mostly in the Americas and some East Asian countries (notably Japan, South Korea, and Taiwan) and SECAM, originally from France and adopted by much of Eastern Europe and the Middle East, but there are various incompatibilities even within these supposed standards. There is no difference between PAL and SECAM for unconverted DIGITAL video including DVDs. However, any analog output to a television set would be in the native format of the country of location. Brazil, Philippines uses a hybrid PAL/NTSC standard called "PAL-M". In Brazil, Philippines, DVDs and video tape are the same as NTSC (without region coding -- see below), but all players and TV sets are useless outside the country unless they have a separate NTSC setting.

Before purchasing any video equipment, read the manual and warranty carefully. For TVs and VCRs don't forget about cable television frequencies; they may not be the same, even if everything else is. Television sets often won't work correctly in another country from where they were sold, even if the voltage and video standard are the same. For example, a television set made for the USA will skip a few channels in Japan. Furthermore, many countries have or are in the process of switching to digital over-the-air broadcasting, ( dates by country). Unless you have an internationally compatible device you may find your expensive looking system is little more than worthless junk in another country because it won't work with your country's broadcast system. Your warranty is probably only valid in the country of purchase, and you may need to return the goods to the place you purchased them from.

The final problem with transporting TVs is that many European countries, notoriously the UK, require a license to watch any live TV (over-the-air, cable, satellite, & even live-streams on the internet). Fees can be hefty (in addition to being charged for the license).

DVD and Blu-Ray, infuriatingly, have completely artificial limitations introduced in the form of region coding, which attempts to limits the region where the discs can be used, as a technique to keep the various regions as separate markets. For example, a Region 1 player in North America will not play a Region 3 DVD from Hong Kong. The workaround are to obtain either a regionless DVD player which ignores the code, purchase multi-region discs (regions 1 & 3 in this case), or better yet, region 0 discs that can be played on any device.

Technically, there is no such thing as a NTSC or PAL DVD disc, as all color information is the same for both. When discs are labeled as such, what they're refering to is the picture size and frame rate (i.e. number of frames per second) that are used in most (but not all!) countries that have TV broadcasts on this same system. Many NTSC players cannot play PAL DVDs, unless that's a specific feature included (many Philips and JVC models include this). PAL DVD players are generally much better at playing NTSC, but it's not a certainty. If all else fails, a computer DVD-ROM can play any DVD movie, though there's a limit on how many times you can change the region code. Unlike analogue television sets, computer monitors can automatically handle both 25 (PAL & SECAM) and 30 (NTSC) frames per second, as well as various picture sizes. This also applies to LCD and plasma "flat panel" television sets, but don't expect their tuner to be compatible outside the country in which they were sold.

Videocameras can usually be charged with both electrical systems so you can record during travels and view it back home. Digital cameras and videocameras can usually output to both PAL, NTSC, and SECAM, so you can view your recording while travelling. Bring an RCA (yellow plug) to SCART adaptor if you plan to view video from a camcorder on a European television set.

VHS and other tape formats, while becoming out of date, still exist. There is no compatibility between NTSC and PAL. Professional conversions will probably cost most than the original. Some manufacturers, such as Philips and Samsung, make or did make several VHS VCR models that will play and record any foreign video format, though these machines are hard to find (try online and mail order) and relatively expensive. Also, you won't be able to make copies of tapes in the format that's not of your country if both the master and the needed copy(s) are of that foreign format. (Unless, of course, you're wealthy enough to afford two of these machines.) You could do a double conversion, but the quality will suffer greatly. One workaround would be to make a DVD in this foreign format, then play it back again to the multi-format VCR. You'll need a computer video capture card capable of both formats (many aren't), DVD production software reset to this foreign format, and a DVD player also capable of playing with an output (not just internal conversion!) of both formats (most aren't, except for the Philips brand) to play it back to the multi-format VCR. If you just want DVD copies, skip the last step of the DVD player playing it back to the VCR, and burn as many copies as you need.

Converting DVDs from one format to another if required, can be done on a computer, or you can get it done professionally. Regular blank discs and software work fine for making copies of a foreign format, as it's all just a bunch of one's and zero's and no different than copying anything else. However, as noted previously, converting it and playing it on a television set is another matter.

Stay safe

The first time you use electrical equipment on a voltage system you haven't used before, watch for excessive heat, strange smells, and smoke. This especially true for those residing in countries with 120V (USA, Canada, Japan, etc.) visiting places with the higher voltage. Smoke is a sure sign your equipment cannot cope with the voltage system.

If your electrical equipment gets very hot, smells of burning (there is a distinct smell of electrically fried circuit boards) or starts to smoke, turn it off at the wall or the main switch immediately, then carefully unplug the equipment. Do not disconnect or unplug by just grabbing the smoking device, its plug or cord, and then unplugging it, as these parts are probably very hot, and the insulation could be melted or unsafe, which could result in electrocution.

You may find your expensive equipment has been fried and needs to be replaced because the wrong voltage was used. However, if the equipment only got hot and did not smoke or produce strange burning smells you may be lucky. Some older devices have fuses that you may be able to replace. New devices, such as gaming consoles, will trip a circuit breaker. Disconnect them from all power and leave them for 60 minutes or so, and the circuit breaker will normally reset.

Do not rely on fuses to protect your equipment. If a fuse does blow, you should have things checked by an electrician before using the suspect equipment again.

In third-world countries with frequent blackouts, it's not at all uncommon for a visitor to plug something in, and have the power go out coincidentially. Always check the neighborhood first, before blaming the appliance or looking at the fuse/circuit breaker.

This is a guide article. It has good, detailed information covering the entire topic. Plunge forward and help us make it a star!

Study guide

Up to date as of January 14, 2010

From Wikiversity

Electrical Systems in Construction is generally broken down to into New Construction, Existing Construction, and Design Build. All designs should meet the standards of client satisfaction, safety, code compliance, aesthetics, and profit.


General Design

A successful design involves a strong understanding of application, safety, layout, growth, flexibility, incorporating old technology with new, and meeting "local" requirements. All Electrical designs needs to be coordinated with the involved trades, such as but not limited to structural, Mechanical Systems/HVACs, Plumbing, and Fire/Life Safety.

Also see Code of Ethics, and Grounding


Branch Circuits can be broken down into Conductors, Overcurrent Devices, and Raceways. Each component has maximum loads which needs to be calculated and properly designed to protect the system. Each component should have proper protection from the elements depending on the local conditions. Conduits need to have their proper insulation and overprotection devices should be kept in panelboards or switchboards.

Also see Panel Schedule and Single Line Diagram

Low Voltage Systems

The Low Voltage Systems (Signals) can include audio/video, voice/data, fire alarms, security, and other low voltage equipment.


The purpose of lighting design should be to provide quality lighting for the task area, to be aesthetic, and minimize energy usage. Lighting is measured terms of footcandles, illuminance, lamp efficacies, footlambert, candlepower or lumens per watt. In theory, light dimishishes as a square function as the distance increases from the source.

Safety Hazards

Electrocutions are the fourth leading cause of death for construction workers in the U.S, so maintaining safe work conditions are important. [1]

  • Overload of Cable Trays
  • Electrical Fires
  • Arc Flash
  • Failure to have electrical power disconnected during demolition
  • Working near underground electrical cables
  • Using heavy equipment near overhead powerlines
  • Failure to deenergize while working with or near live wires.


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