GLOSSARY

The mid-point in the maximum load capacity for a UPS

In an electric power system, a harmonic is a voltage or current at a multiple of the fundamental frequency of the system. Harmonics can best be described as the shape or characteristics of a voltage or current waveform relative to its fundamental frequency. When the waveforms deviate from a sine waveform, they contain harmonics. Harmonic frequencies in the electrical network are a frequent cause of power quality problems, resulting in increased heating of equipment and conductors, variable speed drive failures, and torque pulsations in motors. The fundamental tension or frecuency in Mexico is 60 Hz. Therefore, the harmonics derived from this are multiples of 60, that is, the third harmonic corresponds to 180Hz., the fifth harmonic to 300Hz., etc. Generally, the third harmonic is produced by the unbalance between the phases, that is, if in a three-phase system we use unbalanced one of the three phases with much more load than with the others, we will be producing the third harmonic, both in current and voltage, the too many harmonics are produced by distortions of the fundamental harmonic and / or by low power factor.

We can approximate the concept of harmonic distortion to a “malformation” of the electric current that reaches our homes and businesses. This “malformation” is caused by electronic equipment that consumes electrical energy in a “non-linear” way, that is, in a non-continuous way over time.

The magnitude measured by the hertz is called the frequency and is in this sense, the inverse of the period. One hertz represents one cycle for every second, understanding cycle as the repetition of an event. For example, the fact applies in physics to the measurement of times per second that is repeated in wave (either sound or electromagnetic). In other words; one hertz is the frequency of an oscillation that a particle undergoes in a period of one second.

The term hot swap refers to the ability of some computer components, power supplies or batteries to be installed or replaced without stopping or altering the normal operation of the equipment where they are housed. Example: batteries in a UPS can be replaced without shutting down the unit.