This article is from the Italy FAQ, by Gianluigi Sartori firstname.lastname@example.org, Paolo Fiorini email@example.com with numerous contributions by others.
Last modified: August 13 1993
Luigi Semenzato <luigi@paris.CS.Berkeley.EDU> writes:
Most electrical appliances will need a transformer. Italy's AC is
220V, 50Hz. U.S. is 110V, 60Hz. A transformer can bring 220V, 50Hz
to 110V, 50Hz. The difference between the 50 and 60 Hz is well
tolerated by most appliances (but see below).
Some modern equipment, among which certain models of camcorders and
computers, have a `universal power supply' that will work properly
when plugged anywhere in the world. Check the voltage and frequency
requirements on the appliance itself.
Some items will not work properly even with a transformer. The ones I
know of are clock radios that count the AC cycles to keep the time.
They will run 20% slow in Italy (50 minutes in 1 hour). Transformers
change the voltage, not the frequency. [Not completely true: there
are AC-DC-AC devices that also change the frequency, but they are not
exactly consumer items, so don't look for them at Radio Shack].
Items with large electric motors of the asynchronous type (electric
fans, for instance) will run 20% slower in Italy. (The small motors
in devices like printers or compact disk players run on internally
converted DC, so those are no problem).
For those items that can use a transformer, two types are available:
iron-core transformers, and solid-state transformers.
The iron-core type is generally safe with any appliance, but it is
much heavier than the solid-state type. If the power of the appliance
exceeds about 200W, a iron-core transformer gets rather heavy and it
is usually better to buy it in Italy.
Solid-state transformers are cheaper and much lighter and they are
easily available for power up to 1500W. They should be used for
resistive loads only: clothes irons, soldering irons, hair driers (the
motor has a slight inductive load, but it's sufficiently small
compared with the heating resistor), light bulbs (without a dimmer!).
A large inductive load (like a food processor) is likely to fry the
Solid-state transformers often have a dirty voltage output and may
destroy the power supplies of computers and other electronic