Voltage or “Rated Voltage” refers to the nominal voltage at which the unit will most closely follow the stated specifications. (e.g. 220VAC.) “Voltage Range” indicates the minimum and maximum voltages at which the device will operate. (e.g. 160VAC ~ 240VAC for a 220VAC fan.) It should be noted that in most cases if you run an AC fan for example at lower than nominal voltage the fan will slow down and if you run at a higher than nominal voltage the fan will speed up.
Standard AC voltages in North America are 110, 115, 120V (standard household, outlet current) and 220, 230, 240V (standard household, large appliance current). Note that 110, 115 and 120V are considered equivalent for most applications as are 220, 230 and 240V. Power delivered from a public grid varies from place to place. In rural areas you may measure 110VAC from a wall outlet with a voltmeter while in a city you may be able to measure AC power at levels as high as 127VAC.
There is no need to be concerned about these minor differences however as most AC electrical devices operate over a voltage range with varying efficiency levels. This same concept can be applied to Power Transformers, in which these may output a higher voltage during minimal current draw, but in AC circuits this is typically negligible.
The important thing to note is when a device calls for more than single phase power, to provide its required number of phases such as two-phase or three-phase. Running on less phases then recommended may cause malfunction, premature damage, and other issues. Luckily off-the-shelf products that arrive assembled with a power cord will have the proper end on them to prevent incorrect outlet power.
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Source with further information - Orion Fans Technical Terms