overvoltage

As nouns the difference between surge and overvoltage

is that surge is a sudden transient rush, flood or increase while overvoltage is (physics) 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; overpotential.

As a verb surge

is (lb) to rush, flood, or increase suddenly.

As nouns the difference between overload and overvoltage

is that overload is an excessive load while overvoltage is (physics) 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; overpotential.

As a verb overload

is to load excessively.