Mega MEg 30, Руководство пользователя

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1. Charakteristics
PQ monitor is a multi-function measuring instrument to be used for the measure-
ment and a long-term recording of up to four voltages and four currents, of active
and reactive power and energy in three-phase four-conductor and five-conductor
LV networks, as well as in MV and HV networks. Complying with the EN 50160
standard and with methods of the international standard IEC 61000-4-30, the PQ
monitor analyses all parameters of the voltage quality on voltage inputs U1, U2
and U3.
It registers the events (voltage dips, swells and interruptions) on all the four volt-
ages and it records not only the characteristics of events on voltages as defined by
the standard but also the shapes of all the four voltages and currents at the begin-
ning and at the end of each event – the so-called initial and final details. The initial
detail of an event also comprises the section of time prior to the event while the final
detail also includes the section of time following after this event.
Basing on the measured shapes of currents the PQ monitor enables to assess the
direction of the origination of an event as well as of flicker. By its ability to measure
even small voltages the PQ monitor is also ready for monitoring the voltages be-
tween the neutral conductor and ground. On its fourth current input the PQ moni-
tor enables to carry out the measurement and harmonics analysis of the current of
the neutral conductor. Variably, when using a corresponding sensor the fourth cur-
rent input can also be used for the measurement of other physical quantities, e. g. for
the measurement of temperature.
PQ monitor is provided with a galvanicly separated synchronizing input SYNC.
Its change of state can be registered as an event, too. This makes possible an external
synchronization of the record of shapes of all voltages and of all currents, as well as
a mutual synchronization of a set of several PQ monitors. The PQ monitor has, on its
output, a change-over contact of the polarized relay with a programmable assigna-
tion of the meaning of the signalization.
PQ monitor enables to measure the relationship between the voltage quality and
the power and/or energy. When the preset parameters of voltage quality have been
overpassed, it is possible to switch an external two-state electricity meter or – for op-
erational purposes – to initialize the internal function of the measurement of
“non-quality energy”.
PQ monitor has been designed in the following versions:
MEg 30 – PQ monitor in portable version for LV networks
MEg 31 – PQ monitor in portable version for MV networks
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MEgA Měřicí Energetické Aparáty