3
COMMISSIONING / OPERATION
20
VFC 200
www.krohne.com
06/2019 - 4005059401 - AD VFC200 PB-PA R01 en
Format of SP (Set Point)
•
4 byte float value (for details on float format and status format refer to
Output data
on page
19)
•
1 byte status value (for details on float format and status format refer to
Output data
on page
19)
3.3 Diagnosis
The PROFIBUS device performs internal self-tests. The results are provided as detailed
diagnosis information according to PA Profile 3.02. This diagnosis information is available via
several parameters and can be read by an engineering tool (e.g. DD/DTM). In addition the
diagnosis information is transferred via cyclic services towards the control system (e.g. PLC).
Diagnosis is bitwise coded. Therefore it is possible to report more than one indication
simultaneously. The GSD file contains a text for each diagnosis bit in order to provide a text
message in the control system. The references are defined by the UNIT_DIAG_BIT(i) entries.
They show which bit is set to indicate a special diagnosis event.
The amount and content of the diagnosis information depends on the device configuration.
The active Ident. number and the selected status and diagnosis mode will influence diagnosis
propagation. The following tables show the diagnosis events which are reported for different
settings. The bit number is equal to the counting within the GSD file. It represents the position in
the device-related diagnostic field of the Slave_Diag service.
Bit Number
Su
p
p
or
te
d
Description
Remedy
16
Yes
Error appears
-
17
Yes
Error disappears
-
24
1
Hardware failure electronics
The device or measurement is defective and cannot measure.
Related output values are invalid. Typically a repair or
replacement of the device is required.
Check detailed diagnosis. Restart the device. If the error occurs
again: send the device back to the manufacturer with an
indication of the error.
29
1
Measurement failure
The device or application condition is in a way that the
measurement accuracy may be reduced. But still the
measurement value follows the source. E.g. the device may be
operated outside its specified operating range.
Check detailed diagnosis. Restart the device. If the error occurs
again: send the device back to the manufacturer with an
indication of the error.
34
1
Configuration invalid
-
35
Yes
Restart
Device is restarted because of power-up or warmstart request. In
case of unexpected restart: send the device back to the
manufacturer with an indication of the error.
36
Yes
Coldstart
Device is reset to its Factory/Default settings because of a user
request. Recover user specific parameter settings.
37
Yes
Maintenance required
The device detects problem(s), which are less severe compared to
the diagnosis "Measurement failure". But still the measurement
values are accurate. The output values are still valid, but this may
change in the near future. Check detailed diagnosis to solve the
problem.
