VEGA SOLITRAC 31 4 … 20 mA_HART - four-wire With SIL qualification - Manual (Page 27)

27
6 Functional safety (SIL)
SOLITRAC 31 • 4 … 20 mA/HART - four-wire
43387-EN-131119
•
4 … 20 mA current output
6.4 Safety concept of the parameterization
The following tools are permitted for parameterization of the safety
function:
•
The integrated display and adjustment unit for on-site adjustment
•
The DTM suitable for the signal conditioning instrument in con-
junction with an adjustment software according to the FDT/DTM
standard, e. g. PACTware
Note:
For operation of the SOLITRAC 31 the DTM Collection version 1.67.2
or higher is required. The modification of safety-relevant parameters is
only possible with active connection to the instrument (online mode).
To avoid possible errors during parameterization in a non-safe user
environment, a verification procedure is used that makes it possible
to detect parameterization errors reliably. For this, safety-relevant
parameters must be verified before they are stored in the device. In
normal operating condition, the instrument is also locked against
parameter changes through unauthorized access. This concept ap-
plies to the adjustment on the instrument but also to adjustment with
PACTware with DTM.
For protection against unwanted or unauthorzed adjustment, the set
parameters must be barred from unauthorized access. For this rea-
son, the instrument is shipped in locked condition. The PIN in delivery
status is "0000".
When shipped with a specific parameter adjustment, the instruments
are accompanied by a list with the values deviating from the basic set-
ting. By entering the serial number, the list is available as a download
under "www.vega.com/VEGA-Tools".
After a change, all safety-relevant parameters must be verified and
confirmed via a character string comparison.
The parameter settings of the measurement loop must be docu-
mented. For this purpose, the document "SIL device settings" is at-
tached to each instrument listing all safety-relevant parameters in the
shipping status as well as containing free space for own notes. This
document is also available on our homepage. In addition, a list of the
safety-relevant parameters can be stored and printed via PACTware/
DTM.
For each parameter change, the instrument must be unlocked via a
PIN (see chapter "Setup steps - Lock adjustment"). The device status
is indicated by the symbol of an unlocked or locked padlock.
Warning:
If adjustment is enabled, the safety function must be considered
as unreliable. This applies until the parameterization is terminated
correctly. If necessary, other measures must be taken to maintain the
safety function.
Tool for operation and
parameterization
Reliable parameterization
Safety-relevant param-
eters
Release adjustment
Unsafe device
status