This travel guide is intended strictly as an introduction to international electricity and how it affects a traveler's use of electrical appliances.
There are 3 major electrical differences between the US/Canada (and a few other countries) electricity and the rest of the world:
- Voltage The voltage in US/Canada is generally in the 115 volt range and the rest of the world will be generally in the 220/230/240 volt range.
- Outlet (receptacle) Configurations The outlets in other countries are completely different than those you find in US/Canada and many countries have more than one possible configuration.
- Frequency The US/Canada frequency is 60 Hz. (hertz) while most of the 220/230/240 volt countries have a frequency of 50 Hz. This difference is not generally a big issue for a tourist or business traveler.
How these 3 differences affect you.
US/Canada appliances, for the most part, are designed and manufactured to be used at just 115 volts. If one of these is plugged directly (without a voltage converter or transformer) into a foreign 220/230/240 volt outlet. It will probably, at best, be ruined immediately.
The good news is that many appliances are what they call "multi-voltage" or "dual-voltage". If you have an electrical appliance that you want to use in a foreign country (where the voltage can be 220/230/240) and the appliance is multi-voltage (says input 100-240 volts) or dual voltage (says input 125/250 volts) you usually (if in doubt, verify with manufacturer) only need a plug adapter. The input voltage (watts or amps and frequency, also) information can usually be found on a charger but it could be anywhere on the appliance often on the main body of the appliance where it can be difficult to read.
If the appliance is not multi voltage or dual voltage, you will need either a solid state voltage converter or transformer with the appropriate watt capacity rating. You will need to know the watts or amps required by the appliance in order to get the correct transformer or voltage converter.
Regardless of whether you need a transformer or voltage converter, you will always need a plug adapter. That is a given. Vietnam has more than one possible configuration, so don't be alarmed to see multiple possibilities.
The photo below shows both grounded and ungrounded plug adapters. Grounded plug adapters are needed needed for your grounded appliances and ungrounded adapters can be used with your ungrounded appliances. Grounded appliances have 3 pins on their plugs and ungrounded appliances only have 2 pins on their plugs. Ungrounded plugs are often polarized meaning one of the 2 pins is wider than the other. Most countries outside the US and Canada do not have as many grounded and polarized outlets so you may need both in order to be prepared.
Adapters #1 (4mm) and #6 (5mm) work in most hotel plugs in Vietnam.
Frequency refers to the alternating current (AC) and is a component of electricity that is created at the generating plant. The US/Canada frequency is 60 Hz. (hertz) while most of the 220/230/240 volt countries have a frequency of 50 Hz. This difference is not generally a big issue for a tourist or business traveler.
Usually frequency is only an issue with AC motors (vacuum cleaners, blenders, and other appliances with rotating components) and some older electronic technology. Some AC motors are dual frequency (50/60 Hz.) and unaffected by the difference. It should say somewhere on the motor.
DC (direct current doesn't alternate) motors are also not affected by differences in frequency. Many appliances have rotating components but the motors are DC such as many VCR, tape players, high-end turntables, and many others like that.
There is no practical solution to the frequency problem. An AC motor that is strictly 60 Hz. Will rotate 17% slower in a 50 Hz. Country and it will also run a little hotter. The slower rotation will affect performance and the increased heat will shorten the life of the motor by varying degrees depending on the appliance. These AC motor references include compressors on refrigerators, freezers, air conditioners, etc.