Siemens siprotec 7SA6, Руководство пользователя

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Control During Operation
7-15
7SA6 Manual
C53000-G1176-C156-2
Figure 7-18 Setting statistic values in DIGSI
®
4 — example
7.1.3 Measured Values
Operating measured values are determined in the background by the processor sys-
tem. They can be called up at the front of the device, read out via the operating inter-
face using a PC with DIGSI
®
4, or transferred to a central master station via the sys-
tem interface (if available).
No password entry is required to view the measured values. The values are updated
every few seconds.
Most measured values can be displayed in primary quantities, secondary quantities,
and percentages based on nominal values. A precondition for correct display is that
the nominal values be correctly set in the power system data.
Secondary values are values measured at the device terminals or values calculated
from the latter values.
7.1.3.1 Measured Values
Read-out of
Measured Values In the 7SA6 with maximum functionality the measured values as shown in Table 7-1
are available.
The displacement voltage 3U
0
is either measured directly (3U
0
=
√
3·U
en
, if U
en
is con-
nected to the voltage input U
4
) or calculated (from 3U
0
= U
L1-E
+ U
L2-E
+ U
L3-E
).
The power measurements P, Q are positive, if real power or inductive reactive power
flows into the protected object. This is assuming that this direction has been parame-
terized as “forward”.
The sign of the power factor cos
ϕ
corresponds to the sign of the active power.
For the thermal overload protection the calculated temperature rise values are related
to the tripping temperature rise.
If the device is provided with the synchronism and voltage check function, the charac-
teristical values (voltages, frequences, differences) can be read out.