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Section 3
Vendor-specific implementation
3.3.10
3.3.11
3.3.11.1
3.3.11.2
42
Clock failure bit 12
The quality information bit is set in the IED's real-time clock if the clock has a severe
failure. Do not rely on this time stamp.
Parameter setting group selection
The active parameter setting group can be changed by writing the new setting group
number to 4X register. See Modbus ANSI point list manual for specific mapping. See the
IED documentation for the number of available setting groups. Exception response 3 is
given if the written value is out of range or the setting group changing is blocked.
Time synchronization
The real-time clock inside the IED runs in UTC time. However, the local time is also
known by the IED through the time parameter settings. With Modbus the IED time can be
viewed and set either in local time or UTC time.
Two identical time structures are available in the Modbus memory map: the IED's local
time and the internal UTC time.
Time synchronization can be given either to the local time structure or to the UTC time
structure.
The IED accepts Modbus time synchronization only if the Synch source
setting is set to "Modbus". The parameter can be set via the LHMI path
Configuration > Time > Synchronization > Synch source.
Real-time clock structure
Table 31:
Modbus real-time clock structure
1
Modbus address
Local Time
UTC Time
4xxxx
4xxxx + 19
4xxxx + 1
4xxxx + 10
4xxxx + 2
4xxxx + 11
4xxxx + 3
4xxxx + 12
4xxxx + 4
4xxxx + 13
4xxxx + 5
4xxxx + 14
4xxxx + 6
4xxxx + 15
4xxxx + 7
4xxxx + 16
1. See Modbus ANSI point list manual for specific event record structure mapping.
Writing to real-time structures
The Modbus time synchronization can be done in several ways. Over the serial interface,
the host's synchronization write can be given with the Modbus broadcast address "0".
Thus, all IEDs in the same serial network can be synchronized at the same time.
Register contents
Control register
Year
Month
Day
Hour
Minutes
Seconds
Milliseconds
1MAC052634-MB D
Values
0...2
2000...9999
1...12
1...31
0...23
0...59
0...59
0...999
615/620 series ANSI
Communication Protocol Manual
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