ABB Relion, Техническое руководство

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• V0I0 OR V2I2 . Both negative and zero sequence is activated and working in parallel
in an OR-condition.
• V0I0 AND V2I2 . Both negative and zero sequence is activated and working in series
(AND-condition for operation).
• OptimZsNs . Optimum of negative and zero sequence current (the function that has the
highest magnitude of measured negative and zero sequence current will be activated).
The delta function can be activated by setting the parameter OpDVDI to Enabled . When
selected it operates in parallel with the sequence based algorithms.
As soon as any fuse failure situation is detected, signals FuseFailDetZeroSeq,
FuseFailDetNegSeq or FuseFailDetDVDI, and the specific functionality is released, the
function will activate the output signal BLKV. The output signal BLKZ will be activated
as well if not the internal dead phase detection, DeadLineDet1Ph, is not activated at the
same time. The output BLKV can be used for blocking voltage related measuring
functions (under voltage protection, energizing check, and so on). For blocking of
impedance protection functions, output BLKZ shall be used.
If the fuse failure situation is present for more than 5 seconds and the setting parameter
SealIn is set to Enabled it will be sealed in as long as at least one phase voltages is below
the set value VSealInPU . This will keep the BLKV and BLKZ signals activated as long as
any phase voltage is below the set value VSealInPU . If all three phase voltages drop below
the set value VSealInPU and the setting parameter SealIn is set to Enabled the output
signal 3PH will also be activated. The signals 3PH, BLKV and BLKZ signals will now be
active as long as any phase voltage is below the set value
VSealInPU .
If SealIn is set to Enabled the fuse failure condition is stored in the non-volatile memory
in the IED. At start-up of the IED (due to auxiliary power interruption or re-start due to
configuration change) it uses the stored value in its non-volatile memory and re-
establishes the conditions that were present before the shut down. All phase voltages must
be greater than
VSealInPU before fuse failure is de-activated and resets the signals BLKU,
BLKZ and 3PH.
The output signal BLKV will also be active if all phase voltages have been above the
setting
VSealInPU for more than 60 seconds, the zero or negative sequence voltage has
been above the set value 3V0PU and 3V2PU for more than 5 seconds, all phase currents
are below the setting IDLDPU (operate level for dead line detection) and the circuit
breaker is closed (input 52a is activated).
If a MCB is used then the input signal MCBOP is to be connected via a terminal binary
input to the N.C. auxiliary contact of the miniature circuit breaker protecting the VT
secondary circuit. The MCBOP signal sets the output signals BLKV and BLKZ in order
to block all the voltage related functions when the MCB is open independent of the setting
of
OpModeSel or OpDVDI . An additional drop-out timer of 150 ms prolongs the presence
1MRK 502 048-UUS A
Section 11
Secondary system supervision
339
Technical manual