4 glossary, Glossary – Eppendorf Eporator User Manual
Page 6

Operating instructions
Eppendorf Eporator®
English (EN)
6
1.4
Glossary
A
Arcing
If electrical voltage is applied between two parallel electrodes, a current flows in an
evenly distributed layer. If the voltage exceeds a critical value, this layer contracts to a
narrow circuit with high current density: an electric arc. The electrode material melts at
this location, and explosive evaporation occurs. The cuvette can be destroyed under these
conditions.
E
Electrical field strength
Ratio of potential difference between two electrodes (in V) and the distance between
these electrodes (electrode gap; in cm). However, this only applies if the electrical field is
homogeneous, as with parallel plate electrodes (e.g., in Eppendorf Electroporation
Cuvettes).
T
Time constant
Time during which the voltage decreases to the value U/e.