silly 110-220 question, please
 

i can;t believe i am asking this--really, i can't believe i don't know the answer....but

i have a question about the voltage of my small electric appliances. when it says AC in 100-240v on the little black box part of the electric cord, does that mean that it is suitable for 110 and 220, and that all it needs is an adaptor for the actual plug that goes in the wall? can i assume i don't need to switch a little switch and that it is automatic switching?

btw, what is this feature called, it being suitable for both voltages?

Yes, you should just need an adapter tip. I'm betting you're talking about things like battery chargers?

One thing I have noticed is that my dual-voltage chargers tend to get a little warmer when they're plugged into 220V.

Beware of high voltage!
 

Talk about hot, try running in 240v like Australia. You could fry an egg on my adapter.

In fact, I had to switch to a Targus (universal) adapter, purchased in Australia, because I burned out three, yes three, Kensington (universal) adapters down there. Kensington did replace them under warranty, but obviously they were not designed for that voltage, even though it said so.

Voltage is always stated with a variance, because due to power distribution requirements, it will vary during the day. For instance, in Austrailia it is 240v plus or minus 9%, which means it can rise as high as 261. If you happen to be using it at the time, boom! (off to the Targus store)

Even in Europe, it is 230 plus 6%, or minus 10%, making it between 207 and 244, which is higher than the usual rating.

It also depends on the load hooked up to it. If you are just charging a cellphone then it shouldn't get hot, if you are maxxing it out to charge a 90w laptop then yes; expect a lot of heat and pushing the charger to its limit.

OP - all you will need is the actual PLUG adapter, not an electric adapter.

thank you.