Load (linear) - Load for which voltage form and current form are similar. Voltage and current are related by Ohm's law U(t) = Z x I(t).
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.
Duty Cycle - The operating regime of a battery including factors such as charge and discharge rates, depth of discharge, cycle duration, and length of time in the standby mode.
Distortion (total) - Ratio between the rms value of all harmonics of a non-sinusoidal alternating periodic value and that of the fundamental. This value may also be expressed as a function of the individual distortion of each harmonic Hn= Yn /Y1.
Voltage Depression - An abnormal drop in voltage below expected values during the discharge of a battery.
Ambient Temperature - The average temperature of the surroundings.
Static bypass switch - Power-electronics device that can be used to switch from one source to another without interruption in the supply of power. In a UPS, transfer is from Mains 1 to Mains 2 and back. Transfer without interruption is possible due to the fact that there are no mechanical parts and the ultra-fast switching capabilities of the electronic components.