20.8.2 Function block
IEC09000946.vsd
CHNGLCK
LOCK* ACTIVE
OVERRIDE
IEC09000946 V2 EN
Figure 507: CHNGLCK function block
20.8.3 Signals
Table 848: CHNGLCK Input signals
Name Type Default Description
LOCK BOOLEAN 0 Activate change lock
Table 849: CHNGLCK Output signals
Name
Type Description
ACTIVE BOOLEAN Change lock active
OVERRIDE BOOLEAN Change lock override
20.8.4 Operation principle
The Change lock function (CHNGLCK) is configured using ACT.
The function, when activated, will still allow the following changes of the IED state
that does not involve reconfiguring of the IED:
• Monitoring
• Reading events
• Resetting events
• Reading disturbance data
• Clear disturbances
• Reset LEDs
• Reset counters and other runtime component states
• Control operations
• Set system time
• Enter and exit from test mode
• Change of active setting group
The binary input signal LOCK controlling the function is defined in ACT or SMT:
1MRK502052-UEN B Section 20
Basic IED functions
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Technical manual