Test Sequence C (Simulation And Single-Point Level Detection) - Endress+Hauser Proserve NMS80 Functional Safety Manual

Use in safety instrumented systems
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5.3.3

Test sequence C (simulation and single-point level detection)

Preparatory steps
1. Deactivate SIL mode. Navigate to: Setup → Advanced setup → Deactivate SIL/WHG
and enter the relevant unlocking code (SIL: 7452) for the Reset write protection
parameter.
2. If the safety-related "Analog" signal is used, connect a suitable measuring device
(recommended accuracy better than ±0.1 mA) in the installed circuit.
3. If the safety-related "Digital" signal is used, connect a suitable measuring device
(resistance tester / resistance measurement), (recommended accuracy better than
±0.1 Ω) to the digital output.
4. Determine the safety setting (point level or range monitoring).
Procedure for point level monitoring
1. Navigate to: Expert → Sensor → Sensor diagnostics
2. Setting: Start self check = Yes. If the self check is successful, the following appears:
Result self check= Ok.
 The check has been passed.
3. Read the actual measured value displayed by the device at any level within the
measuring range, e.g. the current level, or determine the actual output current and
compare it with the set point defined by the current level.
 This part of the test is deemed successful if the values are within the required
level of accuracy.
4. Navigate to: Diagnostics → Simulation
5. Setting: Simulation distance on = On. Simulate a level directly below (MAX
monitoring) or directly above (MIN monitoring) the level limit to be monitored
(Simulation distance = corresponding value).
6. Read the output current (mA), record it and assess for accuracy.
7. Read the state of the relay contact (Ω), record it and assess for accuracy.
8. Simulate a level directly above (MAX monitoring) or directly below (MIN monitoring)
the level limit.
9. Read the output current (mA), record it and assess for accuracy.
10. Read the state of the relay contact (Ω), record it and assess for accuracy.
The device has passed the test if the current values and the state of the relay contact
trigger the safety function in step 8 only, and not in step 5.
Procedure for range monitoring
1. Navigate to: Expert → Sensor → Sensor diagnostics
2. Setting: Start self check = Yes. If the self check is successful, the following appears:
Result self check= Ok.
 The check has been passed.
3. Read the actual measured value displayed by the device at any level within the
measuring range, e.g. the current level, or determine the actual output current and
compare it with the set point defined by the current level.
 This part of the test is deemed successful if the values are within the required
level of accuracy.
4. Simulate five levels within the range to be monitored. See the procedure for point
level monitoring (level), steps 4 and 5.
Proserve NMS80
Endress+Hauser