Parallel - Term used to describe the interconnection of cells or batteries in which all the like terminals are connected together. Results in increased capacity.
Temperature Cutoff (TCO) - A protective or safety device (e.g., thermostat, PTC, etc.) which senses temperature (e.g., in a battery) and opens or cuts off the electrical circuit if the specified temperature is exceeded, thus preventing a further rise in temperature due to the charge or discharge of a battery.
Protection index (IP) - Index indicating the capacity of an electrical device to resist environment conditions. It is made up of three digits (e.g. IP 205), each corresponding to a type of environmental risk. The higher the number, the greater the capacity to resist. First digit (0 to 6) - capacity to resist penetration by solid objects. Second digit (0 to 7) - capacity to resist penetration by liquids. Third digit (0, 1, 2, 3, 5, 7, 9) - mechanical strength.
Rectifier/charger - UPS component that draws on the mains the power required to supply the inverter and to float charge or recharge the battery. The alternating input current is rectified and then distributed to the inverter and the battery.
Crest factor (Fc) - Ratio between the peak current value to the rms current value.
Separator - An ionic permeable electronically nonconductive spacer or material which prevents electronic contact between electrodes of opposite polarity in the same cell.
Load power - Apparent power Pu that the UPS inverter supplies under given load conditions. It is less than or equal to the rated output Pn. The ratio Pu/Pn defines the % load of the inverter.