ABB Relion REG670, Applications Manual

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changes from rated value at the ends of the regulation range). In most cases a
value of a = 1.25 serves well.
This calculation gives a setting of Comp that will always initiate an action (start timer)
when the transformers have n tap positions difference.
OperSimTap : Enabling/disabling the functionality to allow only one transformer at a
time to execute a Lower/Raise command. This setting is applicable only to the
circulating current method, and when enabled, consecutive tap changes of the next
transformer (if required) will be separated with the time delay
t2 .
OperUsetPar : Enables/disables the use of a common setting for the target voltage
USet . This setting is applicable only to the circulating current method, and when
enabled, a mean value of the USet values for the transformers in the same parallel
group will be calculated and used.
OperHoming : Enables/disables the homing function. Applicable for parallel control
with the circulating current method, as well for parallel control with the master-
follower method.
VTmismatch : Setting of the level for activation of the output VTALARM in case the
voltage measurement in one transformer bay deviates to the mean value of all voltage
measurements in the parallel group.
tVTmismatch : Time delay for activation of the output VTALARM.
T1RXOP.......T8RXOP : This setting is set On for every transformer that can
participate in a parallel group with the transformer in case. For this transformer (own
transformer), the setting must always be
Off .
TapPosOffs : This setting gives the tap position offset in relation to the master so that
the follower can follow the master’s tap position including this offset. Applicable
when regulating in the follow tap command mode.
MFPosDiffLim : When the difference (including a possible offset according to
TapPosOffs ) between a follower and the master reaches the value in this setting, then
the output OUTOFPOS in the Automatic voltage control for tap changer, parallel
control TR8ATCC function block of the follower will be activated after the time delay
tMFPosDiff .
tMFPosDiff : Time delay for activation of the output OUTOFPOS.
15.4.2.3 TCMYLTC and TCLYLTC general settings
LowVoltTap : This gives the tap position for the lowest LV-voltage.
HighVoltTap : This gives the tap position for the highest LV-voltage.
mALow : The mA value that corresponds to the lowest tap position. Applicable when
reading of the tap position is made via a mA signal.
1MRK 502 071-UEN -
Section 15
Control
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 589
Application manual