Recommendations for LVL-workflow
This article is about the LVL-workflow (see "→LVL - Limited Variability Language"). Observe the following:
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If the complexity of the safety-relevant application is sufficiently low, no explicit module and integration test phase is required because the recommended measures for error prevention in these phases can be integrated in the application test (i.e., when the application is validated). See Warning 1.
See the illustration under "Workflow: Creating a safety-relevant application or library for this application" (box "optional for LVL") for details on which actions and associated work products can be omitted for the LVL-workflow. -
When you are applying the LVL-workflow, the →FBD programming language must be used to integrate existing blocks into a specific application. See Warning 2.
Within FBD, branches can only be created using theEN
input. There are no further elements which influence the control flow (e.g. loops, switches).
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Comply with all recommendations for using FBD. See Warning 3.
If it is not possible to comply with all of the following warnings, apply the full →FVL workflow as illustrated under "Workflow: Creating a safety-relevant application or library for this application".
Warning 1 Neuron Power Engineer must only be used for developing safety-relevant applications and libraries for them when using a full functional safety management (FSM) process and appropriate fault avoiding measures for the target SIL/ASIL. Regardless of the applied workflow, it is imperative to validate the application. The reason for this is that Neuron Power Engineer is used on an unsafe PC. As a consequence, errors in the hardware or the system environment might lead to errors in the application. LCOIII-51569 - The safety mual must contain the information that the user has to validate the safety application before it is used in operation. |
Warning 2 If you want to apply the reduced LVL-workflow for developing safety-relevant applications, make sure that you only implement POUs that are created in →FBD. |
Warning 3 When applying the reduced LVL-workflow for developing safety-relevant applications, make sure that the logic is created in LVL, the logic is kept readable, the simplicity of the application is supported and consider the error handling in FBD. To ensure these aspects for the POUs created in FBD, comply with the following points:
aving of the statement list (-Dlc3.fbdDeactivateStatementListSaving) is not supported |