Alloy - A mixture of several other metals or a metal and a non-metal.
Power Surge - Voltage above 110% of rated RMS voltage for one or more cycles.
Harmonics (current and voltage) - All alternating current which is not absolutely sinusoidal is made up of a fundamental and a certain number of current harmonics which are the cause of its deformation (distortion) when compared to the theoretical sine-wave. For each current harmonic of order n and an rms value In, there is a voltage harmonic with an rms value Un. If Zsn is the voltage source output impedance for the harmonic of the nth order, then - Un = Zsn x In
Crest factor (Fc) - Ratio between the peak current value to the rms current value.
Reactance (subtransient Uscx %, for generator) - Relative measurement (%) of the internal impedance of an AC generator during harmonic phenomena. This reactance, also called the longitudinal subtransient reactance of the generator, is sometimes identified as X"d. For most common generators, the value ranges between 15 and 20%. It can drop to 12% for optimized systems and to 6% for special devices.
Safety Vent - A venting mechanism designed into a cell which activates under specific conditions of abuse to relieve internal pressure.
Constant Current Discharge - A battery discharge regime whereby the current drawn during the discharge remains constant.