Siemens Siprotec 7VK61 Manual page 85

Figure 2-18 Synchro check logic
Operating modes
The closing check for automatic reclosing is possible in one of the following operating modes:
AR SYNC-CHECK
AR Usy1<Usy2>
AR Usy1>Usy2<
AR Usy1<Usy2<
AR OVERRIDE
SIPROTEC, 7VK61, Manual
C53000-G1176-C159-3, Release date 05.2009
Released at synchronism, that is when the critical values AR
maxVolt.Diff, AR maxFreq.Diff, AR maxAngleDiff are within the
set limits.
Released if measuring point Usy1< is de-energised and the measuring point
Usy2> is energised.
Released if measuring point Usy1> is energised and the measuring point
Usy2< is de-energised.
Released if measuring point Usy1< is de-energised and the measuring point
Usy2< is also de-energised.
Released without any check.
2.4 Synchronism and voltage check (optional)
Functions
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