The functions can also be blocked from sending events over IEC 61850 station bus toprevent filling station and SCADA databases with test events, for example during acommissioning or maintenance test.15.5 Change lock function CHNGLCK15.5.1 IdentificationFunction description IEC 61850identificationIEC 60617identificationANSI/IEEE C37.2device numberChange lock function CHNGLCK - -15.5.2 FunctionalityChange lock function CHNGLCK is used to block further changes to the IEDconfiguration and settings once the commissioning is complete. The purpose is toblock inadvertent IED configuration changes beyond a certain point in time.The change lock function activation is normally connected to a binary input.When CHNGLCK has a logical one on its input, then all attempts to modify the IEDconfiguration and setting will be denied and the message "Error: Changes blocked"will be displayed on the local HMI; in PCM600 the message will be "Operation deniedby active ChangeLock". The CHNGLCK function should be configured so that it iscontrolled by a signal from a binary input card. This guarantees that by setting thatsignal to a logical zero, CHNGLCK is deactivated. If any logic is included in the signalpath to the CHNGLCK input, that logic must be designed so that it cannotpermanently issue a logical one to the CHNGLCK input. If such a situation wouldoccur in spite of these precautions, then please contact the local ABB representativefor remedial action.15.5.3 Function blockCHNGLCKLOCK* ACTIVEOVERRIDEIEC09000062-1-en.vsdIEC09000062 V1 ENFigure 271: CHNGLCK function block15.5.4 SignalsTable 504:CHNGLCK Input signalsName Type Default DescriptionLOCK BOOLEAN 0 Activate change lock1MRK 511 287-UEN A Section 15Basic IED functions563Technical manual
