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are similar to those of the BJT.
•
Interface.
In electronics, telecommunications and
hardware, an interface (electronics) is the port (physical
circuit) through which signals are sent or received from one
system or subsystem to another.
•
kVA.
A volt-ampere is the unit used for apparent power in
electrical current. In DC, it is practically equal to real power
but, in AC, it can differ from this depending on the power
factor.
•
LCD.
Liquid crystal display, a device invented by Jack
Janning, who was an employee of NCR. It is an electrical
system for data presentation formed by 2 transparent
conductive layers and a special crystalline material in the
middle (liquid crystal) which have the ability to orientate
light as it passes through.
•
LED.
Light-emitting diode, a semiconductor device (diode)
that emits light that is almost monochromatic, that is to
say, it has a very narrow spectrum when it is polarised
directly and is penetrated by an electric current. The colour
(wavelength) depends on the semiconductor material
used in the construction of the diode, and can vary from
ultraviolet, passing through the visible light spectrum, to
infrared, the latter called IRED (infra-red emitting diode).
•
Circuit breaker.
A circuit breaker is a device capable
of interrupting the electrical current of a circuit when it
exceeds certain maximum values.
•
On-line mode.
A device is said to be on-line when it is
connected to a system, is operative, and normally has its
power supply connected.
•
Inverter.
An inverter is a circuit used to convert DC into AC.
The function of an inverter is to change a DC input voltage
to a symmetrical AC output voltage, with the magnitude
and frequency desired by the user or designer.
•
Rectifier.
In electronics, a rectifier is the element or circuit
that converts AC into DC. This is done by using rectifier
diodes, whether solid state semiconductors, vacuum
valves or gaseous valves, such as those containing mercury
vapour. Depending on the characteristics of the AC power
that they use, they are classified as single-phase when
they are powered by a mains phase or three-phase when
they are powered by three phases. Depending on the type
of rectification, they can be half wave when only one of the
half cycles of the current is used or full wave when both
half cycles are used.
•
Relay.
A relay is an electromechanical device that functions
as a switch controlled by an electrical circuit in which, by
means of an electromagnet, a set of one or several contacts
is activated to enable other independent electrical circuits
to be opened or closed.
•
SCR.
Silicon controlled rectifier, commonly known as a
thyristor, a 4-layer semiconductor device that works as an
almost ideal switch.
•
THD.
Total harmonic distortion. Harmonic distortion occurs
when the output signal of a system does not equal the
signal that entered it. This lack of linearity affects the
waveform because the device has introduced harmonics
that were not in the input signal. Since they are harmonic,
that is to say, multiples of the input signal, this distortion is
not so dissonant and is less easy to detect.
SLC TWIN RT2 T
UNINTERRUPTIBLE POWER SUPPLIES (UPS)
USER MANUAL
