Siemens Add 7 AddFEM - Monitoring and Changeover by Means of Signs of Life

Mode of Operation AddFEM
3-14
AddFEM
C79000–G8076–C900–03
Note
In addition to the bus changeover by the AddFEM the automation processor AP
can change over to active. The AP can specify actively which interface (DP A or
DP B) is to be used.
Table 3-1 Monitoring criteria
No.
Criteria Monitored by...
1 Serious fault in the transmission link, for example,
PROFIBUS DP connector pulled off.
Bus ASIC of the AddFEM
2 Due to a hardware fault the AP sends a global–
control–clear message.
Controller of the AddFEM
3 The sign of life of the AP fails to materialize (simul-
taneous monitoring and changeover mechanism
for AP and AddFEM).
Note: When operated with SIMADYN D the algo-
rithm for generating the signs of life has to be confi-
gured (refer to Section 3.3.2).
Controller of the AddFEM
4 PrmCommand with new assignment of primary and
backup channel.
Note: DPV1_Status_3 Bit 7 (PrmCmd) has to be
set in the parameterization message.
Firmware of the AddFEM
3.3.2 Monitoring and Changeover by Means of Signs of Life
AP A AP B
AddFEM
Output
DP A DP B
DP A DP B
Output
Changeover
after error
in the active
AP
Lz:
0x05/
0x0A
Lz:
0x03/
0x0C
Figure 3-7 Sign of life from Host to AddFEM
The Host sends the sign of life (SoL) cyclically with the period of the program cycle
time of its fastest application t = tcyc to the AddFEM within the regular data
message. The SoL consists alternatively of the Code 1 (hexadecimal value: 0x05
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com