Continuous Test - A test in which a battery is discharged to a prescribed end point voltage without interruption.
Intermittent Test - A test during which a battery is subjected to alternate periods of discharge and rest according to a specified discharge regime.
Power factor (l) - Ratio between the active power P supplied to a load and the apparent power S supplied to said load by an AC power supply.
Bypass (manual) - Manually-operated switch used to supply the load via direct connection to utility power during servicing of the UPS system.
Harmonics (current and voltage) - All alternating current which is not absolutely sinusoidal is made up of a fundamental and a certain number of current harmonics which are the cause of its deformation (distortion) when compared to the theoretical sine-wave. For each current harmonic of order n and an rms value In, there is a voltage harmonic with an rms value Un. If Zsn is the voltage source output impedance for the harmonic of the nth order, then - Un = Zsn x In
Fourier theorem - Theorem stating that any non-sinusoidal periodic function (frequency f) may be represented as a sum of terms (series) made up of - n a sinusoidal term with frequency f, called the fundamental frequency, n sinusoidal terms with frequencies that are whole multiples of the fundamental frequency, (harmonics), n a possible DC component where n is a whole number. n = 1 corresponds to the fundamental, n > 1 to the harmonic of the nth order.
Battery or Pack - Two or more electrochemical cells electrically interconnected in an appropriate series/parallel arrangement to provide the required operating voltage and current levels. Under common usage, the term "battery" is often also applied to a single cell.