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diodes, whether solid state semiconductors, vacuum valves
or gaseous valves, such as those containing mercury va-
pour. 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 recti-
fication, 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 func-
tions as a switch controlled by an electrical circuit in which,
by means of an electromagnet, a set of one or several con-
tacts 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 oc-
curs 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.
SPS ADVANCE R & T
UnInTeRRUPTIbLe PoweR SUPPLy (UPS)
USER MANUAL
