Krytrons can switch currents of up to about 3000 amperes and voltages up to about 5000 volts.

Operation in the avalanche breakdown region is called avalanche-mode operation: it gives avalanche transistors the ability to switch very high currents with less than a nanosecond rise and fall times (transition times).

In an advance that presages the tiniest of computer circuitry possible, researchers at Lucent Technologies have built a transistor in which the layer that switches currents on and off is only one molecule thick.

When switching high currents, the electrodes undergo considerable heat stress, as they are directly involved in the electric arc.

Therefore, switching currents are often required in the range of several hundred milliamperes, or even in the range of amperes.

Scientists at Lucent Technologies' Bell Labs have made a transistor where the layer that switches currents on and off is just one molecule thick, and that promises faster, better chips.

Some important examples include the thyratron, krytron, and ignitron tubes, which are used to switch high-voltage currents.

Spark gaps are also used to switch heavy currents in a Marx generator and to protect electrical appratus.

The effect can be significant when switching large currents very quickly.

This test is important for user safety as modern switchgear is capable of switching large currents.