Flashover normally occurs at 500 °C (932 °F) or 590 °C (1,100 °F) for ordinary combustibles and an incident heat flux at floor level of 20 kilowatts per square metre (2.5 hp/sq ft). An example of flashover is the ignition of a piece of furniture in a domestic room.

What causes flashover voltage?

In the case of direct strike on shield wire or tower structure, a lightning stroke directly strikes the shield wire or tower structure. ... Otherwise, the lightning current will raise the tower to a high voltage above the ground, causing flashover from the tower over the line insulators to one or more phase conductors.

What is flashover voltage?

: the voltage at which a current flashes from electrode to electrode or ground with the formation of a sustained arc.