ABB REC670 Applications Manual page 442

Section 14
Control
436
Setting Values (Range)
TapPosBk Alarm
(automatically Auto Block
reset/manually Auto&Man Block
reset)
CircCurrBk Alarm
(automatically Auto Block
reset) Auto&Man Block
Table continues on next page
Description
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
LowVoltTap and HighVoltTap . When the
parameters
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 (84) 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 TCMYLTC (84) function block, or alternatively by
changing control mode of TR1ATCC (90) or TR8ATCC
(90) function to Manual and then back to Automatic.
When the magnitude of the circulating current exceeds
the preset value (setting parameter
longer time than the set time delay (setting parameter
tCircCurr ) it will cause this blocking condition to be fulfilled
provided that the setting parameter
Enabled . 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 (90) or TR8ATCC (90) outputs
ICIRC and TOTBLK or AUTOBLK will be activated
depending on the actual parameter setting.
1MRK 511 401-UUS A
CircCurrLimit ) for
OperCCBlock is
Bay control REC670 2.2 ANSI
Application manual