Endress+Hauser Proline Prosonic Flow P 500 Functional Safety Manual page 34

Use in protective systems
5.3.5 Testing with a secondary standard and testing of current output 1
• Part 1: Testing with a secondary standard
• Part 2 - Testing of current output 1
Preparation
Byassing of safety function of process control system, to prevent accidental activation of the
safety function.
‣
Deactivate the locked SIL mode →  25.
Test sequence - Part 1: Testing with a secondary standard
The measured values (3 to 5 measuring points) are checked with a secondary standard on an
installed device (mobile calibration rig or calibrated reference device) or on a factory
calibration rig following device removal.
The measured values of the secondary standard and the device under test (DUT) are compared
using one of the following methods:
Comparison by reading off the digital measured value
‣
Compare the digital measured value of the secondary standard against the measured value
display of the DUT at the logic subsystem (process control system or safety-related PLC).
Comparison of the measured value by measuring the current
Requirements for the measuring equipment:
• DC current measuring uncertainty ±0.2 %
• DC current resolution10 µA
1. Measure the current at the DUT using an external, traceably-calibrated ammeter.
2. Measure the current of the DUT at the logic subsystem (process control system or
safety-related PLC).
Evaluation of results - Part 1: Testing with a secondary standard
The amount of deviation between the measured flow rate and the set point must not exceed
the measured error specified for the safety function.
For information on the required measured error for the device, see the "Performance
characteristics" section of the Operating Instructions
‣
Carefully follow the information in the section on "Restrictions for use in safety-related
applications – information on measured errors" →  12.
Test step - Part 2 - Testing of current output 1
The Simulation submenu (→  29) (Diagnostics → Simulation) enables you to simulate,
without a real flow situation, various process variables in the process and the device alarm
mode and to verify downstream signal chains (switching valves or closed-control loops).
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Proline Prosonic Flow P 500 HART
Endress+Hauser