"100-240 VAC" versus "100-127/200-240 VAC"?

Question

Reading the voltage range on the label on electronic devices/appliances, does "100-127/200-240 VAC" actually the same with "100-240 VAC"?

Answer 1

Ah yes, the infamous line voltage select switch, the bane of PC power supplies everywhere.

Those two ranges mean that when you have the select switch set to "115V", then the range is indeed 100-127VAC. Woe be unto you if you forget to change the switch to "230V" when you use the thing overseas - it will destroy the power supply.

This is especially heinous on PCs since their connector is the IEC "C14" socket (sometimes called a "kettle cord") so it's very easy to swap cords and thus plug in the wrong power.

I also see such a selector on hair dryers and other small appliances. At least these tend to have a fixed cord so there's a measure of idiot-proofing on them (though all bets are off when a plug adapter is used.)

On the other hand, a world-standard universal device (like a laptop adapter) is indeed rated for the full range and will say 100-240 (or more typically 100 ~ 240V 50 ~ 60Hz.) You can then safely adapt it to the local source just by changing its cord.

Answer 2

no

they mean exactly what they say.

The first one can have input voltage between 100 and 127 volts, OR between 200 and 240 volts, and usually there is a switch to select one of the two ranges.

The second can have an input of 100 to 240 volts, and there is no switch.

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