ABB ret650, Applications Manual

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The above described scenario does not work if SMAI setting
ConnectionType is Ph-N . If only one phase-earth voltage is
available, the same type of connection can be used but the SMAI
ConnectionType setting must still be Ph-Ph and this has to be
accounted for when setting MinValFreqMeas . If SMAI setting
ConnectionType is Ph-N and the same voltage is connected to all
three SMAI inputs, the positive sequence voltage will be zero and
the frequency functions will not work properly.
The outputs from the above configured SMAI block shall only be
used for Overfrequency protection (SAPTOF), Underfrequency
protection (SAPTUF) and Rate-of-change frequency protection
(SAPFRC) due to that all other information except frequency and
positive sequence voltage might be wrongly calculated.
18.10.3 Setting guidelines
GUID-C8D6C88B-87C6-44C1-804B-CF1594365EE6 v8
The parameters for the signal matrix for analog inputs (SMAI) functions are set via
the local HMI or PCM600.
Every SMAI function block can receive four analog signals (three phases and one
neutral value), either voltage or current. SMAI outputs give information about
every aspect of the 3ph analog signals acquired (phase angle, RMS value,
frequency and frequency derivates, and so on – 244 values in total). Besides the
block “group name”, the analog inputs type (voltage or current) and the analog
input names that can be set directly in ACT.
Application functions should be connected to a SMAI block with same task cycle
as the application function, except for e.g. measurement functions that run in slow
cycle tasks.
DFTRefExtOut : Parameter valid only for function block SMAI1 .
Reference block for external output (SPFCOUT function output).
DFTReference : Reference DFT for the SMAI block use.
These DFT reference block settings decide DFT reference for DFT calculations.
The setting
InternalDFTRef will use fixed DFT reference based on set system
frequency. DFTRefGrp(n) will use DFT reference from the selected group block,
when own group is selected, an adaptive DFT reference will be used based on
calculated signal frequency from own group. The setting
ExternalDFTRef will use
reference based on what is connected to input DFTSPFC.
The setting ConnectionType : Connection type for that specific instance (n) of the
SMAI (if it is Ph-N or Ph-Ph ). Depending on connection type setting the not
connected Ph-N or Ph-Ph outputs will be calculated as long as they are possible to
Section 18
1MRK 504 169-UEN A
Basic IED functions
348 Transformer protection RET650 2.2 IEC
Application manual