The difference has to do more with local wiring then with performance
of the appliance.
In the US, standard (household) outlets have one (hot) phase and neutral,
giving 110V. For industrial applications, particularly for large
induction motors, 3-phase outlet (giving 280V between phases) is used.
The two types of the outlet are shown here:
In other parts of the world, single phase outlet gives 220 and the
'industrial strength' comes to 380 Volts.
When the power (in Watts) is same, an appliance which is
basically a 'heater' will function the same.
If the room in which the unit is to be placed has industrial type wiring,
it would have both types of outlets for both 220V AND 380V. However, the 220V
intended for lights etc, may not have enough power, to accomodate a
This would be a likely reason for ordering 380V, three phase, unit.
Clarification of Answer by
15 Sep 2005 05:32 PDT
Thank you for the kind words.
The answer is "Yes, but".
"But" means: Do not underestimate this. It is not too complicated,
but there are some assumptions here:
1) We assume that the instrument and outlet are for single phase AC current.
(In the reference I gave you previously, there are pictures of single phase
and 3 phase outlets)
2) The transformer must have enough capacity (measured in Watts) to handle
the load, otherwise they overheat or burn or (if they have this
desirable safety feature)they throw the built-in circuit breaker.
3) Transformers that are intended for use by consumers have plugs matching
the voltage so that it is physically impossible to have the wrong voltage
go to the appliance.
Once you start using 'shape adaptors' to defeat this safety feature or you
hook up industrial transformers (which may arrive just with bare wires),
you should know what you are doing. (Electricians are not that expensive
and please do note the disclaimer at the bottom of this page).
4) You may not need a transformer (price and mass go up with power,
about $1 per Watt). A voltage adaptor (not just shape adaptor) may do,
depending on the type of load, and be cheaper.
5) If all conditions above are satisfied, then the same box can function as
a step-up (220 to 380) or step-down (380 to 22v) transformer.
For more info, type the following into (google) search engine:
SEARCH TERMS : Electrical Voltage, Plugs, and Adaptors