UPS (Uninterruptible Power supply) - An electrical device providing an interface between the main power supply and sensitive loads (computer systems, instrumentation, etc.). The UPS supplies sinusoidal AC power free of disturbances and within strict amplitude and frequency tolerances. It is generally made up of a rectifier/charger and an inverter together with a battery for backup power in the event of a mains failure.
Rated Capacity - The number of ampere-hours a battery can deliver under specific conditions (e.g., rate of discharge, end voltage, temperature); usually specified by the battery manufacturer.
Ambient Temperature - The average temperature of the surroundings.
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
Circuit breaker (battery) - DC circuit breaker that protects the battery of a UPS.(back)
Interference (high-frequency) - High-frequency parasitic current that is either conducted (electrostatic origin) or radiated (electromagnetic origin) by a device.
Self-Discharge - The loss of useful capacity of a battery on storage due to internal chemical action (local action).
