Functions
2.39 Inadvertent Energization (ANSI 50, 27)
SIPROTEC, 7UM62, Manual
C53000-G1176-C149-7, Release date 03.2010
269
2.39.2 Setting Notes
General
Inadvertent energizing protection is only effective and available if address 171 INADVERT. EN. is set to
Enabled during configuration. If the function is not required Disabled is set. Address 7101 INADVERT. EN.
serves to switch the function ON or OFF or to block only the trip command (Block relay).
Criteria
Parameter 7102 I STAGE serves to specify the current pickup threshold of the inadvertent energization pro-
tection function. As a rule, this threshold value is set more sensitively than the threshold value of the time-over-
current protection. In this case, the inadvertent energizing protection may only be effective if the device is either
in operational condition 0 or if no nominal conditions have been reached yet. The parameter 7103 RELEASE
U1< serves to define these nominal conditions. The typical setting is about 50 % to 70 % of the nominal voltage.
The parameter value is based on phase-to-phase voltages. A 0 V setting deactivates the voltage tripping. How-
ever, this should only be used if 7102 I STAGE shall be used as 3rd time-overcurrent protection stage, at a
very high setting.
The parameter 7104 PICK UP T U1< represents the time delay for the release of the tripping condition with
undervoltage. The user should select a higher value for this time delay than for the tripping time delay of the
time-overcurrent protection.
The delay time to block the tripping conditions when the voltage is above the undervoltage threshold is set at
7105 DROP OUT T U1<. The inadvertent energizing protection is blocked only after this time in order to enable
a tripping subsequent to connection.
The following figure illustrates the course of events during an unwanted connection at machine standstill and,
in contrast to this, during a voltage collapse on short circuit close to generator terminals.
Figure 2-124 Chronological Sequences of the Inadvertent Energizing Protection
To Next Page
Loading...
Need help?
General
