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LCD.-
LCD acronym of Liquid Crystal Display, device in-
vented 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.
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LED.-
LED acronym of Light Emitting Diode, is a semicon-
ductor device (diode) that emits light almost monochrome
with a very narrow spectrum, it means, when it is direct polar-
ized and it is crossed by an electric current. The colour, (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, re-
ceiving these last ones the denomination of IRED (Infra Red
Emitting Diode).
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Circuit breaker.-
A circuit breaker or switch, is a device
ready to break the electrical current of a circuit when it over-
comes 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.
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Inverter.-
An inverter, is a circuit used to convert direct cur-
rent 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 magni-
tude and frequency by the user or the designer.
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Rectifier.-
In electronic, a rectifier is the element or circuit
that allows to convert the alternating current into direct cur-
rent. 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.
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Relay.-
The relay(in French relais, relief) is an electrome-
chanical device that works as a switch controlled by an elec-
tric circuit where, through an electromagnet, a set of contacts
are moved and it allows to open or to close other independent
electric circuits.
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SCR.-
Abbreviation of «Silicon Controlled Rectifier», called
commonly as Thyristor: semiconductor device of 4 layer that
works as almost an ideal switch.
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THD.-
They are the acronyms of «Total Harmonic Distor-
tion». The total harmonic distortion is done when the output
signal of a system is not equivalent to the one that enter into
it. This lack of linearity affects to the wave shape, because
the equipment has introduced harmonics that they were not
in the input signal. As they are harmonics, it means multiple
of the input signal, this distortion is not so dissonant and it is
more difficult to detect.
USER MANUAL
