Power source (alternate) - Backup source used in the event of a mains failure. The connection time and the duration of the source depend on the type of source used. (back)
Internal Resistance (IR) - The opposition exhibited by a circuit element to the flow of direct current (d.c.). In a cell, the internal resistance is the sum of the ionic and electronic resistances of the cell components.
Blackout - A zero voltage condition lasting for more than two cycles. Same as a power failure
Reliability - Probability that a device will accomplish a required function under given conditions over a given period of time. Rms value of AC current with harmonics The rms value Yrms of a non-sinusoidal alternating current may be determined on the basis of the individual harmonic currents - where Y is the rms value of the fundamental.
Energy - The output capability of a cell or battery, usually expressed in watt-hours.
Thermistor - A temperature sensitive resistor, usually made from specially processed oxides.
Constant Current Discharge - A battery discharge regime whereby the current drawn during the discharge remains constant.