A function key is a key on a computer or terminal keyboard which can be programmed so as to cause an operating system command interpreter or application program to perform certain actions, a form of soft key. On some keyboards/computers, function keys may have default actions, accessible on power-on.
Surge definition, a strong, wavelike, forward movement, rush, or sweep: the onward surge of an angry mob. See more.
In general a surge is a transient wave of current, voltage or power in an electric circuit. In power systems in particular â and this is likely the most common context that we relate surges to â a surge, or transient, is a subcycle overvoltage with a duration of less than a half-cycle of the normal voltage waveform.urges are generally measured in microseconds. Every piece of electrical equipment is designed to operate at a specified nominal voltage such as 120 Vac, 240 Vac, 480 Vac, and so on.