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grig100 · Member 3 Joined: 01 Jan 2015 Posts: 752

Reliable selection of distributed stations for transferring safety-related values
https://support.industry.siemens.com/cs/document/59012254/
In many industrial automation solutions, there are spatial structures where a central control room communicates with various substations. The central control room can select substations, where various actions are performed.
This example shows a possibility for the safety-related switch-over between different stations with the help of flexible F-Link and a non-safety-related HMI.
distributed stations for transferring safety-related values distributed stations for transferring safety-related values

distributed stations for transferring safety-related values distributed stations for transferring safety-related values

Topologies such as these can also be found for example, in dams and locks for ships:
From a central control room located some distance away (several kilometers) various actions can be initiated, limited to a selected substation (eg a ships lock located at a barrage).

A typical requirement could be for instance issuing an Emergency Stop signal from the central control room to a selected substation to set a signal that requests that a ship approaching the door of the lock stops. This emergency stop signal is only applicable for the selected substation.
To transfer this principle to a task involving safety technology can result in the following requirements:
A substation should be selected from the central control room using an HMI device (eg panel).
Initiating the Emergency Stop in the central control room should only act on the selected substation.
This therefore involves requesting a safety-related action (initiating an Emergency Stop) which is based on a non-safety-related action (selecting the substation from a non-safety-related HMI device). It can be seen that for safety-related requirements, additional measures must be integrated into this concept.

By being able to transfer safety-related values via an HMI device in a central control and with Flexible F-link communication, requirements such as these can be implemented based on SIMATIC components. Safety-related communication via Flexible F-Link also facilitates routed communication across additional sections.
The following picture shows the solution of this safety example:
distributed stations for transferring safety-related values distributed stations for transferring safety-related values

A substation (here: 1 or 2) is selected using an HMI device in the central control room. For example, if substation 1 is selected, and Emergency Stop is actuated in the central control room, then the Emergency Stop should only be applicable for substation 1.

The concept required based on permitting a safety-related action to be initiated at a non-safety-related HMI can be used in various applications, for example:
Ships locks and dams
The EC machinery directive also applies to locks and dams.
From a central control room located some distance away (several kilometers) safety-related actions can be initiated (eg Emergency Stop), limited to the selected substation (eg a ships lock located at a barrage).
Selecting various (container) cranes from the drivers cab
From a non-safety-related source (HMI device), the operator can select the required substation (station 1 or 2) in a safety-related fashion. This is done at the HMI in the central control room. To check the plausibility of the station ID characteristic value from a non-safety-related source, it is modified and remodified. The value to be transferred is first modified twice, and transferred to the CPU together with the value that has not been modified. The value that was not modified is then also modified twice in the CPU, and the results are compared with the transferred values.

This procedure is employed to detect any data corruption.
The HMI displays any data corruption that has been identified. If the plausibility check is successful, the checked station ID is displayed for the operator who can then release it. The Emergency Stop that is connected at the central control room only acts on the selected substation.

Documentation and Example Project
https://support.industry.siemens.com/cs/attachments/59012254/59012254_non_safety_hmi_DOC_V2_0_en.pdf
https://support.industry.siemens.com/cs/attachments/59012254/59012254_non_safety_hmi_PROJ_V2_0.zip

https://anonfiles.com/P0v013W2o3/59012254_non_safety_hmi_DOC_V2_0_en_pdf
https://anonfiles.com/dbw916W9o3/59012254_non_safety_hmi_PROJ_V2_0_zip