2 Functions
54
7SA522 Manual
C53000-G1176-C155-3
the presetting is sufficient. This setting is only possible via DIGSI
®
at Additional Set-
tings.
The remaining voltage , which will definitely not be exceeded when the circuit
breaker pole is open, is set in address 3ROH2SHQ9ROWDJH. Voltage transformers
must be on the line side. The setting should not be too sensitive because of possible
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 operation.
Usually the presetting is sufficient. This setting is only possible via DIGSI
®
at Addi-
tional Settings.
The seal-in time 6,7LPHDOO&O (address ) 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 setting is only
possible via DIGSI
®
at Additional Settings.
In address /LQH&ORVXUH the criteria for the internal recognition of line ener-
gization are determined. 0DQXDO&/26( means that only the manual close signal via
binary input or the integrated control is evaluated as closure. ,258RU0DQ&O
implies that in addition, the measured current or voltage are used to determine closure
of the circuit breaker, whereas &%25,RU0& means that , either CB auxiliary
contact status or measured current are used to detect line closure. If the voltage trans-
former are not situated on the line side, the setting &%25,RU0& must be used.
In the case of ,RU0DQ&ORVH only the currents or the manual close signals are
used to recognize closing of the circuit breaker.
While the time 6,7LPHDOO&O (address , refer above) is activated following
each recognition of line energization, 6,7LPH0DQ&O (address ) 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 setting is only possible
via DIGSI
®
at Additional Settings.
Note
For CB Test and automatic reclosure the CB auxiliary contact status derived with the
binary inputs >CB1 ... (FNo. 366 to 371, 410 and 411) are relevant to indicate the CB
switching status. The other binary inputs >CB ... (FNo 351 to 353, 379 and 380) are
used for detecting the status of the line (address ) and for reset of the trip
command (address ). Address 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 functions e.g. 366 and 351 can be allocated to
the same physical input.
For manual closure of the circuit breaker via binary inputs, it can be specified in
address 0$1&/26( whether the integrated manual CLOSE detection checks
the synchronism between the busbar voltage and the voltage of the switched feeder.
This setting does not apply for a close command via the integrated control functions.
If the synchronism check is desired the device must either feature the integrated syn-
chronism check function or an external device for synchronism check must be con-
nected.
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