Who's this Ohm guy you keep mentioning?

December 13, 2011 4:11 PM

I'm moving from the US to Hong Kong and don't want to fry my appliances. What do I need?

Actually, Mrs. Stars and I are trying to figure out which electrical devices to take and which to leave behind. I would like someone with knowledge to confirm I'm right that something like this would be acceptable for lower-power devices, such as an electric toothbrush, while something more like this would be required for something higher powered, such as a food processor.

posted by dust of the stars to Home & Garden (5 answers total)

It's worth noting that many appliances can accept either 110V or 220V, perhaps with a switch on the back to select. In that case, you only need something that connects up the wires; either a cheap "travel adaptor" or a proper IEC cable.

The best way to figure out what an appliance wants is to look for a label on it (or in the instructions) that describes the acceptable voltage inputs and power demands. If the label says 100-250V, you can plug it in with a simple adaptor. If it says 110V, then you will need a voltage converter. To pick the right one, look for the power consumption (60W), and then buy a converter that puts out at least that much power.

I think in many cases you'll find that the adaptors are more trouble than they're worth and that you should just buy a replacement in Hong Kong.
posted by jrockway at 4:39 PM on December 13, 2011

Best answer: Either of these devices should be fine as long as you use them to power appliances within their power rating. As already noted, every electrical appliance will have a label giving you the input voltage & wattage.

What not to take:
High-powered devices [ toasters, grills, microwaves, heaters, hair dryers etc]. Anything rated at more that the 600 watt rating of your 2nd transformer option. A transformer to power this sort of thing will be heavy & expensive.

TV & related video equipment. Only take stuff in this category if you know it will work with the broadcasting standard at your destination,

Stuff that is dependent on 60Hz mains - Very few things fit this category, but some clocks apparently use mains frequency to keep time.
posted by HiroProtagonist at 5:01 PM on December 13, 2011 [1 favorite]

Off topic, but I thought HiroProtagonist might be interested in this link: 60 Hz AC Mains Frequency Accuracy Measurement. Turns out it's super cheap and pretty stable!
posted by jrockway at 6:01 PM on December 13, 2011

I think you've picked out exactly what you need. You won't fry any appliances.

Something I wish someone had told me before I moved to Europe...energy costs are much higher in HK than here. So take it easy on the appliance usage until you get your first bill, and work it out from there.
posted by snsranch at 6:10 PM on December 13, 2011

You need to watch things with motors - ie food processors etc, as a transformer will take care of the voltage change, but will continue to feed it at 50hz, while your motor was designed for 60hz. This can impact the cooling (the motor spins slower than it was designed for, rotating the cooling fan more slowly), so you need to keep an eye on overheating. Things with heating elements are usually not worth it (coffeemaker, hairdryer, toaster, electric kettle, etc.) as the wattage requirements are high, requiring a bigger transformer, and replacements are usually inexpensive.

Almost all electronics should be fine, my lcd tv will take 110-220v, 50-60hz, some will only take one voltage (say 110V), but will accept 50-60hz, so you can easily use a transformer. Don't take a CRT tv. Also, you can use a cable box / DTV box to get the tv channels you need, your tv (assuming a fairly modern flatscreen) should accept both PAL and NTSC, and 50-60Hz HD signals.
posted by defcom1 at 9:07 AM on December 14, 2011