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9.2.
GLOSSARY.
•
AC.-
It is nominated as alternating current to the electrical
current in which the magnitude and direction varies in a cyclic
way. The most common wave shape of the alternating current
is sinewave, because the energy transmission is better.
Neverthe- less, some applications could need other period
wave shapes, like triangular or square.
•
Bypass.-
Manual or automatic, it is the physical junction
between the input and the output electric device.
•
DC.-
The direct current is the continuous electron flow through a
cable between two points with different potential. Unlike the
alternating current, in direct current the electrical loads always
flow in the same direction from the highest potential point to the
lowest one. Although, usually the direct current is identified with
the con- stant current (for example the one supplied by the
battery), it is continuous any current that always maintain the
polarity.
•
DSP.-
It is the acronym of Digital Signal Processor.A DSP is a
system based on a processor or microprocessor that has
instructions in it, a hardware and an optimized software to
develop applications where numerical operations are needed
with very fast speed. Due to this, it is very useful to process
ana- logical signals in real time: in a system that runs in this way
(real time) samples are received, usually coming from an
analogical/ digital converter(ADC).
•
Power factor.-
It is defined as power factor, p.f., of an
alternating current circuit, as the ratio between the active
power, P, and the apparent power, S, or as the cosines of the
angle that make the current and voltage vectors, designating
as cos , being j the value of that angle.
•
GND.-
The term ground, as its name states, refers to the
potential of the earth surface.
•
IGBT.-
The Insulated Gate Bipolar Transistor is a semiconductor
device that is used as a controlled switch in power electronic
circuits. This device has the feature of the gate signal of the
effect field transistors with the capacity of high current and
low voltage saturation of the bipolar transistor, combining an
isolated FET gate for the input and a bipolar transistor as switch
in a single device. The triggering circuit of the IGBT is as the
MOSFET one, while the driving features are like the BJT.
•
Interface.-
In electronic, telecommunications and hardware,
an interface (electronic) is the port (physical circuit) through
which are sent or received signals from a system or subsystems
toward others.
•
kVA.-
The voltampere is the unit of the apparent power in electrical
current. In direct current is almost equal to the real power but in
alternating current can defer depending on the power factor.
•
LCD.-
LCD acronym of Liquid Crystal Display, device invented
by Jack Janning, who was employee of NCR. It is an electric
system of data presentation based on 2 transparent conductor
layers and in the middle a special crystal liquid that have the
capacity to orientate the light when trespassing.
•
LED.-
LED acronym of Light Emitting Diode, is a semiconductor
device (diode) that emits light almost monochrome with a very
narrow spectrum, it means, when it is direct polarized and it is
crossed by an electric current. The color, (wave longitude),
depends on the semiconductor material used in its
construction, being able to vary from the ultraviolet one, going
through the
visible spectrum light, to the infrared, receiving these last ones
the denomination of IRED (Infra Red Emitting Diode).
•
Circuit breaker.-
A circuit breaker or switch, is a device ready
to break the electrical current of a circuit when it overcomes the
maximum set values.
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On-Line mode.-
Regarding to an equipment, it is on line when
it is connected to the system, and it is in operation, and usually
has its power supply turned on.
•
Inverter.-
An inverter, is a circuit used to convert direct current
into alternating current. The function of an inverter is to change
an input voltage of direct current into a symmetrical output
voltage of alternating current, with the required magnitude and
frequency by the user or the designer.
•
Rectifier.-
In electronic, a rectifier is the element or circuit that
allows to convert the alternating current into direct current. This
is done by rectifier diodes, which can be solid state
semiconductors, vacuum or gassy valves as the mercury vapour.
Depending on the features of the alternating current power
supply used, it is classified as single phase, when they are fed
by a single phase electrical mains, or three phase when they are
fed by the three phases. Depending on the rectification type,
they can be half wave, when only one of the current semi-
cycles is used, or full wave, where both semi-cycles are used.
•
Relay.-
The relay(in French relais, relief) is an electromechanical
device that works as a switch controlled by an electric circuit
where, through an electromagnet, a set of contacts are moved and
it allows to open or to close other independent electric circuit.
