Siemens 7SC80 Manual page 238

Functions
2.12 Monitoring Functions
aforementioned address, e.g. 12 %. Irrespective of parameter 2202 2nd HARMONIC, rush blocking will only
occur if the absolute value of the 2nd harmonic is at least 0.125 *Ι
The effective duration of the cross-blocking CROSS BLK TIMER can be set to a value between 0 s (harmonic
restraint active for each phase individually) and a maximum of 180 s (harmonic restraint of a phase blocks also
the other phases for the specified duration).
If the current exceeds the value set in address 2205 I Max, no further restraint will take place for the 2nd
harmonic.
Voltage Transformer Monitoring
The voltage transformer monitoring function is only active if parameter 5510 60VTS is set to ON with NPS.
If set to OFF, the function is deactivated.
The monitoring of 3-phase voltage-transformer faults always works with the variables of the positive sequence
system V1, Ι1.
The function can be blocked via the binary input indication 2531
1- or 2-phase voltage transformer fault:
A failure of a voltage transformer is detected if the voltage exceeds the threshold value 5511 60VTS V2 and
the current falls below the threshold value 5513 60VTS I2 for a period longer than 5518 60VTS T-Delay.
In this case, the indication 2530
3-phase voltage transformer fault:
A 3-phase voltage transformer fault is detected if the voltage of the positive sequence system V1 falls below
the threshold value 5517 60VTS V1 and at the same time, the current of the positive sequence system I1
exceeds the threshold value 5515 60VTS I1 load but remains below the threshold value 5516 60VTS I1
fault fault.
If a 1-, 2-, or 3-phase voltage transformer fault is detected, the indication 1170
238
60VTS Alarm is issued.
.
Nom,sec
>BLOCK 60VTS .
Fail VT Superv. is issued.
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017