Siemens 6MD662, Manual

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Redundant PROFIBUS DP interface
20
SIPROTEC PROFIBUS DP - Bus mapping 6MD662/3/4
C53000-L1840-B011-03
Maximum value of
Start-up time
GlobalSection.DP_Red_TsprimMax
During the redundancy start-up until the initial PRIMARY/BACKUP decision by the
PROFIBUS DP master, both modules have alternating the state S_PRIMARY and
S_WAITING (ref. to chap. 1.6.1).
A state change between the modules is carried out after the time Tsprimary.
Tsprimary starts at 2 s and will be increased by 2 s after each state change until the
configured maximum value TsprimMax.
TsprimMax is entered in 100 ms steps.
If a value is entered which is not divisible by 2 seconds then TsprimMax is rounded up
or down to the next 2 second value by the module firmware. All values less than 2 sec-
onds (including 0) are treated as 2 seconds.
The default value is 20 which corresponds to 2 seconds.
Because this is equal to the Tsprimary start value, all 2 seconds a state change
between S_PRIMARY and S_BACKUP is executed with the TsprimMax default value.
1.3.2 Module status indications
1.3.2.1 Error system interface
If PROFIBUS DP is selected as system interface then the tagging “
SysIntErr
” (Error
System interface) is available in the device parameter set to signal a communication
error to the PROFIBUS DP master.
The reaction of the SIPROTEC device to a communication interruption using the tag-
ging “
SysIntErr
” is described in the manual “SIPROTEC Communication module,
PROFIBUS DP - Communication profile”, chap. “Communication interruption”.
A redundant PROFIBUS DP slave differs from this behavior by the fact that only a
communication error of both modules leads to set the tagging “
SysIntErr
”:
Table 1-3 Tagging “SysIntErr”
Module B
Communication OK Module B
Communication error
Module D
Communication OK “
SysIntErr
” = OFF
OK
“
SysIntErr
” = OFF
OK
Module D
Communication error “
SysIntErr
” = OFF
OK
“
SysIntErr
” = ON
Error
Note:
If the Toggle bit mechanism is activated (Toggle bits, ref. to chap. 1.4.1.4) then a com-
munication error also will be signaled (despite correct PROFIBUS DP data exchange):
•
as long as the Toggle bit mechanism was not started by the master device,
•
when the Toggle bit timer expires.