Novatech Bitronics M87X Series, Руководство пользователя

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ML0021 August 15, 2018
44
Copyright 2018 Bitronics, LLC
The current unbalance is calculated similarly using the current components.
2
(%) 100%
1
U
Uu x
U

4.12 Flicker
Flicker measurements are measured and evaluated according to IEC61000-4-15. Specific
settings for Flicker are found on the “Flicker” page (previously named "Power Quality" tab)
of the Configurator. The Nominal System Frequency should be selected appropriately for
the system in the ”Instrument Transformer Ratio” page (previously the "Advanced" tab) of
the Configurator
.
4.13 Fault Analysis
Fault location and fault type are determined using a single-ended impedance calculation
that is based upon an algorithm using measured values. Following below are the required
line parameters needed to be entered as well as the outputs obtained in the SOE log and
for protocols. Information on triggering and recording for fault location can be found in
section 5.3.7.
4.13.1 Line Parameters
Line parameters for Bus 1 and Bus 2 may be entered independently in the Fault Location
Line Settings area of the 70 Series Configurator (version 2.43 and later). The magnitude
and phase angle of the direct line impedance, Z
d
(positive sequence), and the residual
compensation factor, k
Z0
, are required, where Z
d
is measured in ohms and
k
Z0
= (Z
0
– Z
d
) / 3Z
d
. The zero sequence impedance, Z
0
, is needed when doing the
calculation. In addition, the user may specify the line length and their preferred units of
measure, in place of per unit values (p.u.), for reporting distance in the SOE log.
4.13.2 Peak Current
When the Fault Analysis module is triggered, it will scan for the maximum fundamental
current values in the 10 cycles before and 20 cycles after the trigger point. The maximums
for each of Phase A, Phase B, Phase C, and Residual current are saved. The results are
made available in the SOE log and protocol registers as noted below. Additionally, the
maximum of the three phase (A, B, C) maximums is saved separately and made available
via protocol.
4.13.3 Status Indication and Reset
The availability of measurement points indicating status and which ones can be reset are
indicated as follows: