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I have an appliance rated to be working in 220V-240V, 50/60HZ. The typical power draw is 1000W, max - 1500W.

For the 240V environment where it is now, the typical/max current draw is less than 5/7A.

If I would want to connect it to the US 110V 60Hz socket I would need a step-up voltage transformer with the 10/15A draw.

So the question is - can I have a 'silent' transformer for such a setup? The transformer humming noises would be a major problem if I resort to using it.

On other hand, if I have 3 phases coming into the house from the utility, would it be better to construct 220V socket using two separate 110V phases? I understand that I would need a licensed electrician to do such work.

P.S. Selling the existing appliance and buying one would incur about $500 losses. So if I can get wiring/socket installed for 1/3 of that price, I'd be happy.

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    \$\begingroup\$ This video is related to your question, but just watch it for your entertainment and don't do what he does:) \$\endgroup\$ Aug 5, 2021 at 3:16

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This is trivially (relatively speaking) easy. Do not use a transformer - there are a bunch of reasons why. Most residential service in the US has two hots + neutral going into a breaker panel with 120V (1 hot + neutral) for most "ordinary" receptacles, 240V (2 hots, no neutral) for some large loads (e.g., hot water heater) and combination 120V/240V (2 hots + neutral) for certain (historical reasons, but at this point "inertia") appliances - typically range/cooktop/oven, HVAC, clothes dryer. There are occasional exceptions where a small home will have only 120V. If that's the case, then "transformer" is the answer. But most of the time:

  • Identify an extra space in your panel. That is the hard part. Actually, you will normally need two spaces because 240V requires a double breaker. In most panels, the poles zig-zag through the panel so that consecutive spaces are on opposite hot wires - i.e., any proper 2-space pair will be 240V between the 2 hots. If your panel is full, there are some possible solutions - ask on DIY.
  • Install a proper (must be the right brand/type for your particular panel) double breaker. For this type of appliance, it would likely be a 15A breaker. But you must use a double breaker and not "two 15A 120V breakers side-by-side". That's because you need to make sure that if one hot gets over-current it will cut power to both hots for safety ("common trip").
  • Run appropriate wire to the appliance location. For a 15A circuit (the usual minimum), that is any size 14 AWG or larger. For a 20A circuit, 12 AWG or larger. In most places in the US, this will be NM cable (a.k.a. Romex). Two wire Romex has black and white wires (plus a ground wire). Normally white is for neutral. But a simple 240V circuit like this one is an exception where you can use that white wire (in a cable) as a hot, but it should be marked with black or red tape on each end to make it clear that it is a hot wire. If you use conduit (required in some large cities and other special situations) then you can't use white - both wires must be black, red or some other color besides white, gray or green.
  • Install an appropriate receptacle. Such as this one from Leviton:

Leviton NEMA 6-15

This is a NEMA 6-15 receptacle. The key difference from the usual 5-15 receptacle is that the hot & neutral slots are horizontal instead of vertical. Nothing magical about that, but it makes it impossible to accidentally plug a 240V appliance into a 120V receptacle or a 120V appliance into a 240V receptacle. There is a similar 6-20 receptacle for 20A circuits.

  • Install a 6-15 plug on the appliance.

There are a bunch of other general "how to wire things up safely" rules along the way. But the basic point is "installing a 240V receptacle for a 240V appliance" is the best way to solve the problem.

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    \$\begingroup\$ Thank you very much for such a detailed answer. \$\endgroup\$ Aug 6, 2021 at 4:30
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In the US and Canada we rarely have three phase power in our homes.

Normal domestic power is from a 240 V centre-tapped transformer, with the centre tap being the Neutral - so we have two "Hot" wires each 120 V from Neutral,but 240 V between them.

Heavy loads such as electric stoves, electric water heaters and clothes dryers will use 240 V.

You could get a 240 V outlet installed for your appliance, but it would probably be more practical (and likely less expensive) to buy a 120 V version of the appliance when you get to the US.

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  • \$\begingroup\$ Thanks for your input. Selling/buying this thing would cost me min $500 or more, that's why I decided to go with the transformer/wiring option. \$\endgroup\$ Aug 6, 2021 at 4:02

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