Duty Cycle - The operating regime of a battery including factors such as charge and discharge rates, depth of discharge, cycle duration, and length of time in the standby mode.
UPS (parallel without redundancy) - A UPS made up of several (n) parallel-connected UPS units with equal output ratings (P) and each equipped with its battery, for large loads. The total output is equal to the number of units multiplied by their individual output (n x P). In this configuration, no UPS unit is redundant.
Earthing system TT - Earthing system in which the neutral and the exposed conductive parts are directly earthed. The installation must be de-energized immediately in the event of an insulation fault.
Noise level - Acoustical decibel level of a source of noise, measured according to the applicable ISO standard.
Positive Temperature Coefficient (PTC) - A thermally reactive device which becomes highly resistive at a specific temperature or current.
Thermistor - A temperature sensitive resistor, usually made from specially processed oxides.
AB5 - A metal alloy (e.g., LaNi5) capable of undergoing a reversible hydrogen absorption/desorption reaction as the battery is charged and discharged, respectively.