2.16 Function Control and Circuit Breaker Test
223
7SD610 Manual
C53000-G1176-C145-4
the setting of the parameter address 1134 Line Closure (see Section 2.1.4 at
margin heading „Circuit Breaker Status“).
The phase currents and the phase-to-earth voltages are available as measuring quan-
tities. A flowing current excludes that the circuit breaker is open (exception: A fault
between current transformer and circuit breaker). If the circuit breaker is closed, it may,
however, still occur that no current is flowing. The voltages can only be used as a cri-
terion for the de-energized line if the voltage transformers are installed on the feeder
side. Therefore, the device only evaluates those measuring quantities that provide in-
formation on the status of the line according to address 1134.
But a change-of-state, such as a voltage jump from zero to a considerable value (ad-
dress 1131 PoleOpenVoltage) or the occurrence of a considerable current (ad-
dress 1130 PoleOpenCurrent), can be a reliable indicator for line energization as
such changes can neither occur during normal operation nor in case of a fault. These
settings can only be changed via DIGSI at Display Additional Settings.
The position of the auxiliary contacts of the circuit breakers directly indicate the posi-
tion of the circuit breaker. If the circuit breaker is controlled single-pole, energization
takes place if at least one contact changes from open to closed.
The detected energization is signalled through the message „Line closure“ (No.
590). The parameter 1132 SI Time all Cl. is used to set the signal to a defined
length. These settings can only be changed via DIGSI at Display Additional Set-
tings. Figure 2-97 shows the logic diagram.
In order to avoid that an energization is detected mistakenly, the state „line open“,
which precedes any energization, must apply for a minimum time (settable with the
address 1133 T DELAY. SOTF). The default setting for this enable delay is 250 ms.
This setting can only be changed using DIGSI at Additional Settings.
Figure 2-97 Generation of the energization signal
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