All About Transformers

By Mrs. Rachel Bondy

To save money on buying new appliances when relocating overseas, many customers ask whether American 110 volt appliances will work properly overseas on 220 volts, with a step-down transformer.

In some cases, the answer is “yes”, though U.S. current is 60Hz (cycles), and overseas current, 50Hz. The cycle indicates the speed of the current. A transformer does not change the cycles.

This is of utmost importance when using a transformer with time controlled appliances such as microwaves, clockradios, breadmakers or any appliance with a built-in timing device. The timing will then, of course, be off, making the appliance not very useful.

For appliances that are speed controlled, such as mixers, blenders and food processors, this difference in cycles will slow it down about 10%. Technically, it will still operate, but the resulting stress on the motor will significantly shorten it’s life.

But remember, it’s only worthwhile to take along appliances that are in new condition, in order to get the longest use out of it.

When buying a transformer, be sure to first check the wattage amount of each appliance. This information can usually be found on the bottom or the back of the machine. If only the amp amount is provided (running amps), you can arrive at the correct wattage by using the formula, Amps x Voltage = Wattage.

The transformer must have a higher wattage rating than the appliance. It’s strongly recommended to go at least 20% higher, in order to safely handle electrical surges. You can use several appliances on one transformer, but again, be sure that their combined wattage is less than the transformer’s wattage capacity.
If there’s not enough coverage, the appliance(s) will burn out rather quickly.

You can use a transformer with heat producing appliances, such as toasters, coffeemakers (without timers), hot water kettles, grills, etc. However, because these are high wattage machines, it may be more cost effective to just replace them with a new, 220 volt, appliance.

There is a special type of transformer that’s only for use with non-motorized heat producing appliances, such as hair straighteners and curlers, sterilizers, bottle warmers etc. This type of transformer is lightweight, inexpensive and can handle up to 1600 watts. This is meant for temporary,  short term use. (longer term use will blow the appliance).
This type of transformer is not meant for use with hair dryers, because of the motorized blower fan.

Many items may be “Dual Voltage” and can be used worldwide without a transformer. Some of these automatically adjust to the proper current in the full range of 110-240 volts, while some may need to be adjusted with the built-in voltage selector switch.
These may include shavers, hair dryers, travel irons, boomboxes, portable DVD players, as well as chargers for cellphones, digital cameras and ipods etc.
Electronics that are meant to be taken with you when traveling are usually dual voltage.
Most desktop computers have the selector switch, while most laptop computers adjust voltage automatically.

All these items are very helpful when traveling, but remember to stock up on the correct plugs that fit the wall sockets in other countries. For most of Europe and Israel, you will need plugs with 2 rounded pins, for other regions you may need 3 round pins. (In the U.S. and Canada, the plugs have 2 flat pins).


We carry Seven Star transformers, a good quality value brand, as well as Todd Systems, a premium brand. These are simply the best transformers on the market.

Transformers need to have open air around them. They should not be used next to a radiator, inside a box, under furniture, or surrounded in a bookshelf, etc.
Transformers are designed to operate and feel warm to the touch. This is not a cause for concern.

It is generally less costly (but less convenient) to use one larger transformer for several appliances, rather than using a separate transformer for each. However, transformers intended for use with a permanently placed, frequently run load, such as a refrigerator, washing machine, etc., should be left attached and used for that appliance only.