ABB RELION Series, Техническое руководство

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U_A
U_B
U_C
I_A
I_B
I_C
GUID-91ED3E3D-F014-49EE-B4B0-DAD2509DD013 V1 EN
Figure 361: Functional module diagram
10.3.4.1 Phase mode setting
PHQVVR is designed for both single-phase and polyphase ac power systems, and
selection can be made with the
Phase mode setting, which can be set either to the
"Single Phase" or "Three Phase" mode. The default setting is "Single Phase".
The basic difference between these alternatives depends on how many phases are
needed to have the voltage variation activated. When the
Phase mode setting is
"Single Phase", the activation is straightforward. There is no dependence between the
phases for variation start. The
START
output and the corresponding phase start are
activated when the limit is exceeded or undershot. The corresponding phase start
deactivation takes place when the limit (includes small hysteresis) is undershot or
exceeded. The
START
output is deactivated when there are no more active phases.
However, when Phase mode is "Three Phase", all the monitored phase signal
magnitudes, defined with Phase supervision , have to fall below or rise above the limit
setting to activate the
START
output and the corresponding phase output, that is, all
the monitored phases have to be activated. Accordingly, the deactivation occurs when
the activation requirement is not fulfilled, that is, one or more monitored phase signal
magnitudes return beyond their limits. Phases do not need to be activated by the same
variation type to activate the
START
output. Another consequence is that if only one
or two phases are monitored, it is sufficient that these monitored phases activate the
START
output.
10.3.4.2 Variation detection
The module compares the measured voltage against the limit settings. If there is a
permanent undervoltage or overvoltage, the
Reference voltage setting can be set to
1MRS758755 A
Section 10
Power quality measurement functions
REC615 and RER615 681
Technical Manual