Siemens SITRANS P DS III - Settings

Functional safety
8.3 Settings
SITRANS P DS III with PROFIBUS PA
132 Operating Instructions, 06/2013, A5E00053276-07
Operational reliability
According to IEC 61511-1, Section 11.4.4, the hardware fault tolerance (HFT) can be
reduced by one (values in brackets) for transmitters and final controlling elements with
complex components if the following conditions apply to the device:
● The device is proven in operation.
● The user can configure only the process-related parameters, e.g. control range, signal
direction in case of a fault, limiting values, etc.
● The configuration level of the firmware is blocked against unauthorized operation.
● The function requires SIL of less than 4.
See also
General functional safety (http://www.siemens.com/safety)
Functional safety in process instrumentation (http://www.siemens.com/SIL)
8.3
Settings
Introduction
Take the following measures when using the device for functional safety.
Procedure
1. Setting safety-relevant parameters
2. Checking the safety function
3. Enabling write protection
Checking the safety function
Note
You should check the saf
ety function while the device is mounted, if possible. If this is not
possible, you can also check the safety function when the device is not mounted. Make sure
that the transmitter is mounted in the same position for testing as it is in in the system.
Requirement
Key lock and write protection (Page 116) are canceled.
We recommend that:
● You check the status for warnings and alarms.
● You check the measured value limits.