ABB ret650, Applications Manual

Page: 223 / 392

Setting Values (Range) Description
TapPosBk
(automatically
reset/manually
reset)
Alarm
Auto Block
Auto&Man Block
This blocking/alarm is activated by either:
1. The tap changer reaching an end position i.e. one of
the extreme positions according to the setting
parameters
LowVoltTap and HighVoltTap. When the
tap changer reaches one of these two positions
further commands in the corresponding direction will
be blocked. Effectively this will then be a partial
block if Auto Block or Auto&Man Block is set. The
outputs POSERRAL and LOPOSAL or HIPOSAL
will be activated.
2. Tap Position Error which in turn can be caused by
one of the following conditions:
• Tap position is out of range that is, the indicated
position is above or below the end positions.
• The tap changer indicates that it has changed more
than one position on a single raise or lower
command.
• The tap position reading shows a BCD code error
(unaccepted combination) or a parity fault.
• The reading of tap position shows a mA value that is
out of the mA-range. Supervision of the input signal
for MIM is made by setting the MIM parameters
I_Max and I_Min to desired values, for example,
I_Max = 20mA and I_Min = 4mA.
• Very low or negative mA-values.
• Indication of hardware fault on BIM or MIM module.
Supervision of the input hardware module is
provided by connecting the corresponding error
signal to the INERR input (input module error) or
BIERR on TCMYLTC or TCLYLTC function block.
• Interruption of communication with the tap changer.
The outputs POSERRAL and AUTOBLK or TOTBLK will
be set.
This error condition can be reset by the input RESETERR
on TCMYLTCfunction block, or alternatively by changing
control mode of TR1ATCC or TR8ATCC function to
Manual and then back to Automatic.
CircCurrBk
(automatically
reset)
Alarm
Auto Block
Auto&Man Block
When the magnitude of the circulating current exceeds
the preset value (setting parameter
CircCurrLimit) for
longer time than the set time delay (setting parameter
tCircCurr) it will cause this blocking condition to be fulfilled
provided that the setting parameter OperCCBlock is On.
The signal resets automatically when the circulating
current decreases below the preset value. Usually this
can be achieved by manual control of the tap changers.
TR1ATCC or TR8ATCC outputs ICIRC and TOTBLK or
AUTOBLK will be activated depending on the actual
parameter setting.
MFPosDiffBk
(manually reset)
Alarm
Auto Block
In the master-follower mode, if the tap difference between
a follower and the master is greater than the set value
(setting parameter
MFPosDiffLim) then this blocking
condition is fulfilled and the outputs OUTOFPOS and
AUTOBLK (alternatively an alarm) will be set.
Setting parameters for blocking that can be set in TR1ATCC or TR8ATCC under
setting group Nx in PST/ local HMI are listed in table
28 .
1MRK 504 169-UEN A
Section 11
Control
Transformer protection RET650 2.2 IEC 217
Application manual