Operation Principle - Hitachi Relion 650 Series Technical Manual

Section 14
Basic IED functions
Table 373: SMAI_80_12 Non group settings (basic)
Name
GlobalBaseSel
DFTReference
ConnectionType
AnalogInputType
Table 374: SMAI_80_12 Non group settings (advanced)
Name
Negation
MinValFreqMeas
14.10.6

Operation principle

Every SMAI can receive four analog signals (three phases and one neutral value), either voltage or
current. The AnalogInputType setting should be set according to the input connected. The signal
received by SMAI is processed internally to obtain 244 different electrical parameters, for example
RMS value, peak-to-peak, frequency and so on. The activation of BLOCK input resets all outputs to
0.
SMAI_80 does all the calculation based on nominal 80 samples per line frequency period, this gives
a sample frequency of 4 kHz at 50 Hz nominal line frequency and 4.8 kHz at 60 Hz nominal line
frequency.
The output signals AI1...AI4 in SMAI_80_x function block are direct outputs of the connected input
signals GRPxL1, GRPxL2, GRPxL3 and GRPxN. GRPxN is always the neutral current. If GRPxN is
not connected, the output AI4 is zero. The AIN output is the calculated residual quantity, obtained as
a sum of inputs GRPxL1, GRPxL2 and GRPxL3 but is equal to output AI4 if GRPxN is connected.
The output signals AI1, AI2, AI3 and AIN are normally connected to the analog disturbance recorder.
The output signal AI3P in the SMAI function block is a group output signal containing all processed
electrical information from inputs GRPxL1, GRPxL2, GRPxL3 and GRPxN. Applications with a few
exceptions shall always be connected to AI3P.
The input signal REVROT is used to reverse the phase order.
396
Values (Range) Unit
1 - 6 -
InternalDFTRef -
DFTRefGrp1
DFTRefGrp2
DFTRefGrp3
DFTRefGrp4
DFTRefGrp5
DFTRefGrp6
DFTRefGrp7
DFTRefGrp8
DFTRefGrp9
DFTRefGrp10
DFTRefGrp11
DFTRefGrp12
External DFT ref
Ph-N -
Ph-Ph
Voltage -
Current
Values (Range) Unit
Off -
NegateN
Negate3Ph
Negate3Ph+N
5 - 200 %
The SMAI function block always calculates the residual quantities in case only the
three phases (Ph-N) are connected (GRPxN input not used).
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Step Default
1 1
- InternalDFTRef
- Ph-N
- Voltage
Step Default
- Off
1 10
1MRK 511 557-UEN Rev. A
Description
Selection of one of the Global Base
Value groups
DFT reference
Input connection type
Analog input signal type
Description
Negation
Limit for frequency calculation in % of
UBase
D0E8595T201305151403 v1
Technical Manual
PID-3044-SETTINGS v1