overvoltage

noun

1. (countable, uncountable)The difference between the electric potential of an electrode or cell under the passage of a current and the thermodynamic value of the electrode or cell potential in the absence of electrolysis.
2. (countable, uncountable)The hazardous condition that occurs when the voltage in a circuit is raised above that for which it was designed.

verb

1. To raise the voltage of a circuit beyond that for which it was designed.