If the voltage exceeds a certain threshold, such as during a lightning termination to the conductor, it "jumps" the insulators and passes to earth.

If this voltage exceeds the dielectric breakdown strength of the insulating material of the line then an arc will occur.

As the gap was reduced further, the voltage required to cause an arc began to rise and again exceeded its original value.

The accelerators usually have several stages, with voltage between the stages not exceeding 200 kV to prevent field emission.

The LED is on when the voltage across the load exceeds 1.8 V (the indicator circuit introduces some error).

When the voltage exceeds that level, the electrons behave differently, creating a much lower resistance.

However, this is only approximate, and the voltage can exceed the capacity of a single lamp at speed, causing failure.

Once the voltage exceeds the dielectric strength of the gases, the gases become ionized.

If a valve is biased within the linear region and the input signal's voltage exceeds this region, overdrive and non-linear clipping will occur.

The device operates by shunting excess current when the induced voltage exceeds the avalanche breakdown potential.