Test Sequence B (Simulate The Level) - Endress+Hauser Proserve NMS80 Functional Safety Manual

Use in safety instrumented systems
24
5.3.2

Test sequence B (simulate the level)

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 "Digital" safety-related 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 diag
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. Navigate to: Diagnostics → Simulation
4. Setting: Simulation distance on = On. Simulate a level directly below (MAX
monitoring) or directly above (MIN monitoring) the level limit to be monitored. To
simulate the level, you must calculate the level to the distance (value entered) (level
= empty calibration - distance).
5. Read the output current (mA), record it and assess for accuracy.
6. Read the state of the relay contact (Ω), record it and assess for accuracy.
7. Simulate a level directly above (MAX monitoring) or directly below (MIN monitoring)
the level limit.
8. Read the output current (mA), record it and assess for accuracy.
9. Read the state of the relay contact (Ω), record it and assess for accuracy.
The test has been passed successfully if the current values and the state of the relay
contact trigger the safety function in step 7 only, and not in step 4.
Procedure for range monitoring
1. Navigate to: Expert → Sensor → Sensor diag → Start self check
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. Simulate five levels within the range to be monitored. See the procedure for point
level monitoring, steps 3 and 4.
4. For every level value, read the output current (mA) and the switch status of the relay
(Ω), record them and assess for accuracy.
The test has been passed successfully if the current values and the switch status of the
relay in step 4 are within the required accuracy limits.
Relay self-monitoring
Relay self-monitoring must only be performed if the "Digital" safety-related signal is used.
Example of terminal designation: If the Digital IO module used for the safety function is
installed in slot D and contacts 3 and 4 are used, Digital D3-4 must be used instead of
Digital Xy-z below.
Proserve NMS80
Endress+Hauser