ABB 615 Series ANSI, Technical Manual

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1MAC050144-MB C
Section 8
Measurement functions
615 series ANSI 579
Technical Manual
8.12.4.4 Variation validation
The validation criterion for voltage variation is that the measured total variation duration
is between the set minimum and maximum durations (Either one of VVa dip time 1, VVa
swell time 1 or VVa Int time 1, depending on the variation type, and VVa Dur Max). The
maximum variation duration setting is the same for all variation types.
Figure 312 shows voltage dip operational regions. In Figure 310, only one voltage
dip/swell/Int set is drawn, whereas in this figure there are three sub-limits for the dip
operation. When Voltage dip set 3 is undershot, the corresponding PICKUP_x and also the
DIPST outputs are activated. When the TRMS voltage magnitude remains between
Voltage dip set 2 and Voltage dip set 1 for a period longer than VVa dip time 2 (shorter
time than VVa dip time 3), a momentary dip event is detected. Furthermore, if the signal
magnitude stays between the limits longer than VVa dip time 3 (shorter time than VVa Dur
max), a temporary dip event is detected. If the voltage remains below Voltage dip set 1 for
a period longer than VVa dip time 1 but a shorter time than VVa dip time 2, an
instantaneous dip event is detected.
For an event detection, the TRIP output is always activated for one task cycle. The
corresponding counter and only one of them (INSTDIPCNT, MOMDIPCNT or
TEMPDIPCNT) is increased by one. If the dip limit undershooting duration is shorter than
VVa dip time 1, VVa swell time 1 or VVa Int time 1, the event is not detected at all, and
if the duration is longer than VVa Dur Max, MAXDURDIPCNT is increased by one but
no event detection resulting in the activation of the TRIP output and recording data update
takes place. These counters are available through the monitored data view on the LHMI or
through tools via communications. There are no phase-segregated counters but all the
variation detections are registered to a common time/magnitude-classified counter type.
Consequently, a simultaneous multiphase event, that is, the variation-type event detection
time moment is exactly the same for two or more phases, is counted only once also for
single-phase power systems.
.
Figure 312: Voltage Dip operational regions
In Figure 313, the corresponding limits regarding the swell operation are provided with the
inherent magnitude limit order difference. The swell functionality principle is the same as
Voltage dip set 1
Voltage dip set 2
Voltage dip set 3
Voltage
xVref
Time (ms)
0
0
VVa Dur Max VVa dip time 3 VVa dip time 1 VVa dip time 2
1.00
Instantaneous
dip
Temporary
dip Momentary
dip
Maximum duration
dip