
Diagnostics
Monitoring for interruption of PROFIBUS communication
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EDS82ZAFPC201 EN 4.0
9.3
Monitoring for interruption of PROFIBUS communication
Permanent interruption of communication
If the PROFIBUS communication is interrupted permanently, e.g. by cable breakage or
failure of the PROFIBUS master, no process data are transmitted to the slave in the
"Data_Exchange" state.
When the monitoring time has expired, the reaction parameterised in
C1514
is executed.
The slave only reacts if ...
1. the user has activated the reaction by selecting "TRIP (fault)", "controller inhibit
(CINH)" or "quick stop (QSP)".
2. the slave is in the "Data_Exchange" state.
3. the user has correctly configured the monitoring time in the master.
If one of these preconditions is not met, the reaction to the absence of cyclic process data
telegrams from the master is not executed.
Short−time interruption of the communication
POWER ON
WAIT_PRM
WAIT_CFG
DATA_EXCH
Slave_Diag
Get_Cfg
Set_Slave_Add
Slave_Diag
Chk_Cfg, not o.k.
Set_Prm, not o.k.
Chk_Cfg, o.k.
Slave_Diag
Set_Prm
Get_Cfg
2133PFB006
The master detects the communication fault and puts the slave into the "WAIT_PRM"
state of the DP state machine after only a few microseconds (see above).
Only when the state chain of the DP state machine ending the "Data_Exchange"
(DATA_EXCH) state has been completed, the monitoring time calculated for the slave (in
the millisecond range) continues to run.
The monitoring time does
not
continue to run when the slave does not reach the
"Data_Exchange" state due to repeated communication faults (e.g. caused by loose
contact).