Change Lock Chnglck; Application; Denial Of Service Dos - ABB RELION 670 Series Applications Manual

Section 21
Security
The information can, in addition to be viewed on the built in HMI, also be retrieved with the aid
of a PC with PCM600 installed and by using the Event Monitoring Tool. The PC can either be
connected to the front port, or to the port at the back of the IED.
21.3

Change lock CHNGLCK

21.3.1

Application

Change lock function CHNGLCK is used to block further changes to the IED configuration once
the commissioning is complete. The purpose is to make it impossible to perform inadvertent
IED configuration and setting changes.
However, when activated, CHNGLCK will still allow the following actions 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 controlling the function is defined in ACT or SMT. The CHNGLCK function is
configured using ACT.
LOCK
When CHNGLCK has a logical one on its input, then all attempts to modify the IED
configuration 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 denied by active
ChangeLock". The CHNGLCK function should be configured so that it is controlled by a signal
from a binary input card. This guarantees that by setting that signal to a logical zero,
CHNGLCK is deactivated. If any logic is included in the signal path to the CHNGLCK input, that
logic must be designed so that it cannot permanently issue a logical one to the CHNGLCK
input. If such a situation would occur in spite of these precautions, then please contact the
local ABB representative for remedial action.
21.4

Denial of service DOS

21.4.1 Application
The denial of service functions (DOSFRNT, DOSLANAB and DOSLANCD) are designed to limit
the CPU load that can be produced by Ethernet network traffic on the IED. The communication
facilities must not be allowed to compromise the primary functionality of the device. All
inbound network traffic will be quota controlled so that too heavy network loads can be
698
Binary input signal that will activate/deactivate the function, defined in ACT or SMT.
1MRK 504 152-UEN B
GUID-B48775D0-ACF0-49C6-A7F6-69AF37F1C68F v1
GUID-51EEC9C7-8ECF-4546-BC26-326861654340 v4
GUID-8C333BC0-AA7A-4ED1-A772-18C22E8EEE62 v4
GUID-64F4D905-9F73-4073-B8F6-8D373155316A v4
Application manual