Constant Resistance Discharge - A battery discharge regime whereby the resistance of the equipment load remains constant throughout discharge.
Intermittent Test - A test during which a battery is subjected to alternate periods of discharge and rest according to a specified discharge regime.
Voltage-Keyed - A system which incorporates a mechanical identifier on batteries and devices to ensure only batteries of the correct voltage are connected to the device.
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.
Earthing system IT - Earthing system in which the neutral is isolated from the earth or connected to the earth via a high impedance and the various exposed conductive parts are connected to the earth via individual earthing circuits. An alarm must signal the appearance of a first insulation fault. The installation must be de-energized immediately in the event of a second insulation fault.
Alloy - A mixture of several other metals or a metal and a non-metal.
Crest factor (Fc) - Ratio between the peak current value to the rms current value.
