Samson 3730-4, Mounting And Operating Instructions

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Fault/diagnostic alarm
Default setting acc. to Pro-
file 3.01 Condensed Status
Classified
Diagnosis
Yes No
Function activated
Initialization active 0xBC GOOD_NON_SPECIFIC • 1) –
Diagnostic function active 0xBC GOOD_NON_SPECIFIC •
1)
–
1)
Can be classified between GOOD_FUNCTION_CHECK and BAD_FUNCTION_CHECK in firmware K 1.10 and
higher. See FEATURE_SELECT parameter on page 136.
14.5 Diagnostics with PROFIBUS-DP protocol
Generated alarms are classified and summarized in the PROFIBUS Profile 3.01 and “Con-
densed status and diagnostic messages“ extension.
The diagnostic approach complying with PROFIBUS-DP includes the following types of diag-
nostic transfer:
4
The DP master class 1 reads the diagnostics of the DP slave while the cyclic data
exchange is being set up.
4 In case of an active diagnostic alarm, the slave responds during the data exchange with a
high-prioritized response telegram.
The master requests a diagnosis as a result to continue afterwards with the normal data
exchange.
The diagnostic alarm is composed of the standard diagnosis according to PROFIBUS DP and
the user-specific diagnosis. The first six octets of the diagnostic alarm are assigned to the
standard diagnosis, essentially providing a statement about the state of the cyclic connection.
Special attention is given to the DIAG.ext bit (octet 1). The slave uses this bit to indicate to the
master that the output data are invalid. As a result, the master interrupts the cyclic data ex-
change to read out the diagnostic data. The master first returns to cyclic data exchange when
the DIAG.ext bit is reset by the slave.
If, however, the DIAG.ext bit is set to 0, the existing data are treated as status information by
the system. For the Type 3730-4 Positioner, this behavior can be determined by the
FEATURE_SELECT parameter. By selecting the option “DIA_MAINTENANCE_ALARM sets
DIAG_EXT bit“, the DIAG_EXT bit is set when the DIA_MAINTENANCE_ALARM bit has been
determined. Deactivate this option if all the data of the positioner should be used as status in-
formation.
104
EB 8384-4 EN
PROFIBUS-PA communication