Page 99 - Sace Emax 2 Catalogue

SUPERVISION AND CONNECTIVIT Y 5/21

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Energy Measurements

Network Analyzer

— Distortions of the voltage value (sags, swells)
and/or frequency can have fatal consequences,
Thanks to the Network Analyzer especially for process industries, leading to pos-
function available in all Ekip Touch sible production stoppages with consequently ex-
pensive downtime, damage to motor drives and
trip units, the quality of energy damage to PLCs. Examples of process industries
based on harmonics, micro- that can be badly hit by voltage instabilities in-
clude the plastics, petrochemicals, textiles, pa-
interruptions or voltage dips is per, semiconductor, and glass industries.
monitored without the need for Voltage sag is defined as when the value of the
voltage is reduced below the rated one for a cer-
dedicated instrumentation. tain amount of time. Similarly, voltage swell is de- 05

Thanks to Network Analyzer, effective preventive fined as when the voltage is increased above the
and corrective action can be implemented through rated value for a certain amount of time.
accurate analysis of faults, thereby improving the RMS voltage values and frequency are two funda-
efficiency of the system. mental features of a voltage signal, but the “pure-
ness” of the voltage waveform is also an import-
ant point. An ideal voltage waveform should be a
Applications perfect sinusoid, but this is not something that is
Electrical equipment is designed for optimum op- normally seen in the real world. Frequencies other
eration under constant and uniform voltage level, than the fundamental are always present.
as close as possible to the rated value. In addi- These frequencies are called harmonics: a har-
tion, industrial equipment, working on a three monic of a signal is a component frequency of the
phase supply, requires the three phase voltage wave spectrum that is a multiple of the funda-
levels to be balanced. Power quality is a descrip- mental frequency. Harmonic content is an issue
tion of how well a power system complies with that is becoming increasingly debated: techno-
the above ideal conditions. Power quality issues logical developments in the industrial and house-
can have negative consequences on the compo- hold field have led to the spread of electronic
nents and on the energy efficiency of the network. equipment which, due to their operating princi-
Thus, power quality monitoring is becoming more ples, absorb a non-sinusoidal current (non-linear
important in modern power systems, and will be a load). Such current causes a non-sinusoidal volt-
key part of the smart grid of the future. age drop on the supply side of the network with
In particular, power quality evaluation includes the consequence that the linear loads are also
the following aspects: supplied with a distorted voltage.
• Deviations of voltage average value from the
rated value
• Short decreases (sags) or increases (swells) of
voltage value
• Voltage unbalance, i.e., difference in voltage val-
ues between different phases
• The presence of current and voltage harmonics.