Hitachi Relion 650 Series Technical Manual page 295

1MRK 511 557-UEN Rev. A
IEC19000760 V2 EN-US
Figure 129: Detection of precise current inception instant
The function initially detects the breaker state change from the RMS value of the electrical feedback
signal: The breaker is assumed closed as soon as the RMS value rises above the absolute
CloseCThreshold value. From the instant of closed state detection, the function backtracks the
samples until the absolute value is less than or equal to CloseFThreshold. This sample with
corresponding timestamp is considered the inception instant.
In addition to the actual values, ACBMSCBR also provides the predicted pre-strike angle and
predicted making time for the operation, as detailed in
published on receiving the closing command CLCMDINP, and the actual values are published as
soon as the inception is detected.
Open operation electrical monitoring
This feature detects the instant of current interruption (arc extinction), from which it derives the
interruption time and arcing time, as shown in
Technical Manual
Inception instant
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CloseCThreshold
CloseFThreshold
Section 12.18.7.11.1. The predicted values are
Figure 130.
Section 12
Monitoring
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