Siemens siprotec 7SD5 User Manual page 65

be very sensitive. Otherwise this setting must be increased correspondingly. Usually
the presetting is sufficient. This parameter can only be altered with DIGSI
ditional Settings.
The residual voltage PoleOpenVoltage, which will definitely not be exceeded when
the circuit breaker pole is open, is set in address 1131. Voltage transformers are pre-
sumed to be on the line side. The setting should not be too sensitive because of pos-
sible parasitic voltages (e.g. due to capacitive coupling). It must in any event be set
below the smallest phase-earth voltage which may be expected during normal opera-
tion. Usually the presetting is sufficient. This parameter can only be altered with
DIGSI
The seal-in time SI Time all Cl. (address 1132) determines the activation period
for enabling protection functions following each energization of the line (e.g. fast trip-
ping high-current stage). This time is started by the internal circuit breaker switching
detection when it recognizes energization of the line or by the circuit breaker auxiliary
contacts, if these are connected to the device via binary input to provide information
that the circuit breaker has closed. The time should therefore be set longer than the
circuit breaker operating time during closing plus the operating time of this protection
function plus the circuit breaker operating time during opening. This parameter can
only be altered with DIGSI
In address 1134 Line Closure the criteria for the internal recognition of line ener-
gization are determined. Only with ManCl means that only the manual close signal
via binary input or the integrated control is evaluated as closure. I OR U or ManCl
means that additionally the measured currents or voltages are used to determine
closure of the circuit breaker, whereas CB OR I or M/C implies that either the cur-
rents or the states of the circuit breaker auxiliary contacts are used to determine
closure of the circuit breaker. If the voltage transformers are not situated on the line
side, the setting CB OR I or M/C must be used. In the case of I or Man.Close
only the currents or the manual close signals are used to recognize closing of the
circuit breaker.
Address 1135 Reset Trip CMD determines under which conditions a trip command
is reset. If CurrentOpenPole is set, the trip command is reset as soon as the current
disappears. It is important that the value set in address 1130 PoleOpenCurrent
(see above) is undershot. If Current AND CB is set, the circuit breaker auxiliary
contact must send a message that the circuit breaker is open. It is a prerequisite for
this setting that the position of the auxiliary contacts is allocated via a binary input.
While the time SI Time all Cl. (address 1132, refer above) is activated following
each recognition of line energization, SI Time Man.Cl (address 1150) is the time
following manual closure during which special influence of the protection functions is
activated (e.g. increased reach of the distance protection). This parameter can only be
altered with DIGSI
Note
For CB Test and automatic reclosure the CB auxiliary contact status derived with the
binary inputs >CB1 ... (No. 366 to 371, 410 and 411) are relevant for the circuit breaker
test and for the automatic reclosure to indicate the CB switching status. The other
binary inputs >CB ... (No. 351 to 353, 379 and 380) are used for detecting the status
of the line (address 1134) and for reset of the trip command (address 1135). Address
1135 is also used by other protection functions, e.g. by the echo function, energization
in case of overcurrent etc. For use with one circuit breaker only, both binary input func-
tions, e.g. 366 and 351, can be allocated to the same physical input.
7SD5 Manual
C53000-G1176-C169-1
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under Additional Settings.
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under Additional Settings.
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under Additional Settings.
2.1 General
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under Ad-
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