Siemens siprotec 7SA522 User Manual page 396

Table 6-9
Measured values
I , I , I
L1 L2 L3
3I
0
I , I
1 2
3I0
sen
I , I
Y P
U , U , U
L1–L2 L2–L3 L3–L1
U , U , U
L1–E L2–E L3–E
3U
0
U voltage at the measuring input U
X
U , U
1 2
R, X operational resistance, reactance
S, P, Q apparent, real, and reactive power MVA, MW,
ϕ
cos
f
1 ) acc. to address  (refer to Sub-section 6.1.3)
3 ) with consideration of the factor  ,,SK &7 (refer to Sub-section 6.1.1)
4 ) with consideration of the factor  8SK  8GHOWD (refer to Sub-section 6.1.1)
Metering of Energy
Operational measured values
phase currents
earth currents
pos. and neg. seq. currents
sensitive earth current
transformer star point current or
earth current in the parallel line
line voltages
phase-earth voltages
displacement voltage
pos. and neg. seq. voltages
power factor
frequency
The computation of the operational measured values is also executed
during an existent system fault in intervals of approx. 0,5 s.
The 7SA522 integrates the calculated power which is then made availa-
ble with the "Measured Values". The components are listed in table 6-10.
The signs (positive = export, negative = import) are defined the same as
for the powers.
Please take into consideration that 7SA522 is, above all, a protection de-
vice. The accuracy of the measured values depends on the current trans-
former (normally protection core) and the tolerances of the device. The
metering is therefore not suited for tarif purposes. The counters can be
reset to zero or any initial value (see Subsubsection 7.1.3.3).
primary secondary
A A
A A
A A
A mA
A A
kV V
kV V
kV V
kV V
4
kV V
Ω Ω
—
MVAR
(abs) (abs)
Hz Hz
2
) acc. to address (refer to Sub-section 6.1.3)
% referred to
rated operational current
rated operational current
rated operational current
rated operational current
rated operational current
rated operational voltage
/√3
rated operational voltage
·√3
rated operational voltage
/√3
rated operational voltage
/√3
rated operational voltage
—
√3·U
·I
N N
rated operational values
—
rated frequency
7SA522 Manual
C53000-G1176-C119-2
1
)
1
)
1
)
1 3
) )
1 3
) )
2
)
2
)
2 4
) )
2
)
2
)
1 2
) )