7SA522 Manual
C53000-G1176-C119-2
The computation of the operational measured values is also executed
during an existent system fault in intervals of approx. 0,5 s.
Metering of Energy 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).
Table 6-9 Operational measured values
Measured values
primary secondary % referred to
I
L1
, I
L2
, I
L3
phase currents A A rated operational current
1
)
3I
0
earth currents A A rated operational current
1
)
I
1
, I
2
pos. and neg. seq. currents A A rated operational current
1
)
3I0
sen
sensitive earth current A mA rated operational current
1
)
3
)
I
Y
, I
P
transformer star point current or
earth current in the parallel line
A A rated operational current
1
)
3
)
U
L1–L2
, U
L2–L3
, U
L3–L1
line voltages kV V rated operational voltage
2
)
U
L1–E
, U
L2–E
, U
L3–E
phase-earth voltages kV V rated operational voltage /√3
2
)
3U
0
displacement voltage kV V rated operational voltage ·√3
2
)
4
)
U
X
voltage at the measuring input U
4
kV V rated operational voltage /√3
2
)
U
1
, U
2
pos. and neg. seq. voltages kV V rated operational voltage /√3
2
)
R, X operational resistance, reactance ΩΩ —
S, P, Q apparent, real, and reactive power MVA, MW,
MVAR
—
√3·U
N
·I
N
rated operational values
1
)
2
)
cos ϕ power factor (abs) (abs) —
f frequency Hz Hz rated frequency
1
) acc. to address (refer to Sub-section 6.1.3)
2
) 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 8SK8GHOWD (refer to Sub-section 6.1.1)