SMAI1BLOCKDFTSPFCREVROT^GRP1L1^GRP1L2^GRP1L3^GRP1NSPFCOUTG1AI3PG1AI1G1AI2G1AI4G1NNEUTRALPHASEL3PHASEL2PHASEL1UL1L2SAPTOFU3P*BLOCKBLKTRIPTRIPSTARTBLKDMAGNFREQTRM_40.CH7(U)SAPTOF(1)_TRIPIEC10000060-2-en.vsdxIEC10000060 V2 EN-USFigure 214: Connection exampleThe above described scenario does not work if SMAI settingConnectionType isPh-N. If only one phase-earth voltage is available, the same type of connectioncan be used but the SMAIConnectionType setting must still bePh-Ph and thishas to be accounted for when settingMinValFreqMeas. If SMAI settingConnectionType isPh-N and the same voltage is connected to all three SMAIinputs, the positive sequence voltage will be zero and the frequency functionswill not work properly.The outputs from the above configured SMAI block shall only be used forOverfrequency protection (SAPTOF), Underfrequency protection (SAPTUF) andRate-of-change frequency protection (SAPFRC) due to that all otherinformation except frequency and positive sequence voltage might be wronglycalculated.21.11.3 Setting guidelines GUID-C8D6C88B-87C6-44C1-804B-CF1594365EE6 v8The parameters for the signal matrix for analog inputs (SMAI) functions are set via the localHMI 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 analogsignals acquired (phase angle, RMS value, frequency and frequency derivates, and so on – 244values 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 theapplication 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 settingInternalDFTRef will use fixed DFT reference based on set system frequency.DFTRefGrp(n) willuse DFT reference from the selected group block, when own group is selected, an adaptiveDFT reference will be used based on calculated signal frequency from own group. The settingExternalDFTRef will use reference based on what is connected to input DFTSPFC.1MRK 511 358-UEN A Section 21Basic IED functions447Application manual
