ABB Relion 670 Series Applications Manual page 430

Section 15
Control
Load voltage adjustment (LVA)
LVAConst1 : Setting of the first load voltage adjustment value. This adjustment of the target
USet is given in percent of UBase .
value
LVAConst2 : Setting of the second load voltage adjustment value. This adjustment of the target
USet is given in percent of UBase .
value
LVAConst3 : Setting of the third load voltage adjustment value. This adjustment of the target
USet is given in percent of UBase .
value
LVAConst4 : Setting of the fourth load voltage adjustment value. This adjustment of the target
USet is given in percent of UBase .
value
VRAuto : Setting of the automatic load voltage adjustment. This adjustment of the target value
USet is given in percent of UBase , and it is proportional to the load current with the set value
reached at the nominal current
RevAct
OperationRA : This setting enables/disables the reverse action partial blocking function.
tRevAct : After the reverse action has picked up, this time setting gives the time during which
the partial blocking is active.
RevActLim : Current threshold for the reverse action activation. This is just one of two criteria
for activation of the reverse action partial blocking.
Tap changer control (TCCtrl)
Iblock : Current setting of the over current blocking function. In case, the transformer is
carrying a current exceeding the rated current of the tap changer for example, because of an
external fault. The tap changer operations shall be temporarily blocked. This function typically
monitors the three phase currents on the HV side of the transformer.
DayHuntDetect : Setting of the number of tap changer operations required during the last 24
hours (sliding window) to activate the signal DAYHUNT
HourHuntDetect : Setting of the number of tap changer operations required during the last
hour (sliding window) to activate the signal HOURHUNT
tWindowHunt : Setting of the time window for the window hunting function. This function is
activated when the number of contradictory commands to the tap changer exceeds the
specified number given by
NoOpWindow : Setting of the number of contradictory tap changer operations (RAISE, LOWER,
RAISE, LOWER etc.) required during the time window
HUNTING.
Power
P> : When the active power exceeds the value given by this setting, the output PGTFWD will be
activated after the time delay
which effectively means that a negative value of
in the reverse direction. This is shown in figure
for all values to the right of the setting. Reference is made to figure
forward and reverse direction of power through the transformer.
424
I2Base .
NoOpWindow within the time tWindowHunt .
tPower . It shall be noticed that the setting is given with sign,
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tWindowHunt to activate the signal
P> means an active power greater than a value
217 where a negative value of
212
1MRK 511 401-UEN Rev. K
P> means pickup
for definition of
Bay control REC670
Application manual