Pulse Current - A periodic current drain of higher than normal drain rates.
Distortion (total) - Ratio between the rms value of all harmonics of a non-sinusoidal alternating periodic value and that of the fundamental. This value may also be expressed as a function of the individual distortion of each harmonic Hn= Yn /Y1.
Inverter - UPS subassembly that recomposes a sine-wave output (regulated and without breaks) using the DC current supplied by the rectifier-charger or the battery. The primary elements of the inverter are the DC/AC converter, a regulation system and an output filter.
Primary Battery - A battery which is not intended to be recharged and is discarded when the battery has delivered all of its electrical energy.
Top-Up Charge - A low rate charge following the main charge, designed to ensure maximum capacity.
Current Density - The current per unit active area of the surface of an electrode.
Safety installation - Installation supplying electrical equipment which may have a direct effect on the safety of users and must therefore remain energized even in the event of a mains failure. In general, characteristics concerning the power supply and conditions for transfer to the safety source for such electrical equipment are covered by applicable regulations.