VAMP 259 - Reverse Power and Underpower Protection P

2.16 Reverse power and underpower
protection P< (32)
2 Protection functions
Technical description
108
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VM259.EN007
Recorded values of the undervoltage stages (8 latest faults)
U<, U<<, U<<< (27)
Parameter
Value
Unit
Description
yyyy-mm-dd
Time stamp of the recording, date
hh:mm:ss.ms
Time stamp, time of day
Flt
%Un
Minimum fault voltage
EDly
%
Elapsed time of the operating time
setting. 100% = trip
PreFlt
%Un
Supervised value before fault, 1 s
average value.
SetGrp
1
2
Active setting group during fault
2.16. Reverse power and underpower
protection P< (32)
Reverse power and underpower function is sensitive to active
power. For reverse power function the pick-up value is
negative. For underpower function a positive pick-up value is
used. Whenever the active power goes under the pick-up value,
the stage picks up and issues a start signal. If the fault
situation stays on longer than the delay setting, a trip signal is
issued.
The pick-up setting range is from –200 % to +200 % of the
nominal apparent power Sn. The nominal apparent power is
determined by the configured voltage and current transformer
values.
Equation 2.16-1
3
PrPr

imaryRatedimaryRatedn
CTVTS
There are two identical stages available with independent
setting parameters.