Safety Concept Of The Parameterization - Siemens SITRANS LG250 Operating Instructions Manual

Tool for operation and
parameterization
Safe parameterization
Safety-relevant param-
eters
Unlock adjustment
Unsafe device
status
PBD-51041388
The following inputs/outputs are permitted:
•
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:
To operate SITRANS LG250, 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 parameterisation in a non-safe operat-
ing environment, a verification procedure is used that enables reliable
detection of parameter adjustment errors. The safety-relevant pa-
rameters have to be verified after they are saved in the instrument. In
normal operating condition, the instrument is also protected (locked)
against inadvertent or unauthorized parameter changes. This concept
applies to adjustment directly on the instrument as well as adjustment
with PACTware and DTM.
To prevent unintentional or unauthorized adjustment, the set param-
eters must be protected from unauthorized access. For this reason
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
setting.
All safety-relevant parameters must be verified after a change.
The parameter settings of the measurement loop must be document-
ed. You can find a list of all safety-relevant parameters in the delivery
status in chapter "Setup with the display and adjustment module"
under "Additional adjustments - Reset". 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.
In delivery status, the PIN is 0000.
Warning:
If adjustment is enabled, the safety function must be considered
as unreliable. This applies until the parameterisation is terminated
correctly. If necessary, other measures must be taken to maintain the
safety function.
SITRANS LG250 - Operating Instructions
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