Endress+Hauser Proline Prosonic Flow P 500 Functional Safety Manual page 30

Use in protective systems
2. Compare current at output 1 with this default value.
Comparing the current values
The current values can be compared using one of the following methods:
• Measure the current of the DUT at the logic subsystem (process control system or safety-
related PLC).
• Measure the current at the DUT using an external, traceably-calibrated ammeter.
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Compare the current values.
Connecting the measuring equipment and external testing
• Connecting the measuring equipment in the measuring circuit
• External check of the passive current output
Requirements for the measuring equipment:
• DC current measuring uncertainty ±0.2 %
• DC current resolution10 µA
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 3 External verification taking the example of a passive current output
1 Automation system with current input (e.. g. PLC)
2 Power supply unit
3 Ammeter
4 Transmitter
1. Connect the ammeter to the transmitter by looping it in series into the circuit.
2. Connect the power supply unit.
Evaluation of results - Part 2: Testing of current output 1
The amount of deviation between the measured current and the set point must not exceed the
measured error specified for the safety function. The deviation should not exceed ±1 % /
±300 µA.
‣
Note data relating to measured error→  14.
Connecting the test
1. Re-activate the locked SIL mode→  19.
2. Deactivate bypassing of safety function of process control system.
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