Baker Hughes Masoneilan 12400 Series, Instruction Manual & Safety Manual

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•
The repair time (MTTR) after a device has failed is 24 hours.
•
The architectural constraint type for the 12400 Series level instrument is B (Low demand).
•
The hardware fault tolerance of the device is 0.
•
To avoid unwanted or unauthorized modification, the set parameters must be protected. Therefore, the hardware
lock jumper must be set in the secure (locked) position.
•
Proof test interval:

1 years.
•
Safety accuracy: 2% of full span.
•
Only a single component failure will fail the entire 12400 Series level instrument.
•
Failure rates are constant, wear-out mechanism is not included.
•
Propagation of failures is not relevant.
•
All components that are not part of the safety function and can not influence the safety function (feedback immune)
are excluded.
•
The stress levels are average for an industrial environment and can be compared to the Exida profile 3 with
temperature limits within the manufacturer's rating. Other environmental characteristics are assumed to be within
manufacturer's rating.
•
A practical fault test can demonstrate the correctness of the failure effects during the FMEDA and the diagnostic
coverage provided by the online diagnostics.
•
The HART protocol is only used for setup, calibration and diagnostics purposes, not for safety critical operation.
•
The application program in the logic solver is constructed in such a way that Fail High and Fail Low failures are
detected regardless of the effect, safe or dangerous, on the safety function.
•
Materials are compatible with process conditions.
•
The device is installed, calibrated and maintained per manufacturer's instructions.
•
External power supply failure rates are not included.
•
Worst-case internal fault detection time is one hour.
8.4.2. H
ARDWARE AND FIRMWARE REVISIONS SUITABLE FOR
SIL
APPLICATIONS
Hardware revision must be revision 1 or later.
Firmware revision must be revision 1.1.2 or later.
8.4.3. H
ARDWARE LOCK JUMPER ADJUSTMENT
The lock jumper function allows or disables any setting parameter changes. It is located in the front view of the instrument
head, behind the main cover. The hardware lock jumper must be set in the secure (locked) position to be used as a SIL 2
instrument.
When set to the secure position, shorting the two-pin header, access to Setup and Clear Error modes are not permitted by the
local interface or by the remote HART communication. It is not allowed to write any new data into the instrument memory.
Pushbuttons, ValVue and any HART
®
handheld are locked out, except to read data (normal, view data and view errors menus).
In such case, LOCK message is indicated on LCD display when the user presses a button.
Parameters setting lock jumper
Figure 19
Front view of instrument head, with
main cover removed