Introducing Indicators and Flexible Indicators

When assets and shop floor systems are created in SAP Digital Manufacturing, and machine data tags are mapped to indicators, it is possible to exchange information between the systems. This means that data is exchanged from SAP Digital Manufacturing to the shop floor layer and the other way round.

When it comes to shop floor Integration, we must distinguish between two general use cases:

1. Trigger Automation from SAP Digital Manufacturing

   In the first use case, indicators are actively read and written from SAP Digital Manufacturing to the shop floor layer. This means that the trigger for when the automation sequence should be executed comes from SAP Digital Manufacturing, and with this the data is read or written.

   Example: Order-specific data is stored in a set point indicator in SAP Digital Manufacturing. This means that the set point provides the temperature data for heating an oven in a production line for a specific production order. When it comes to production execution at the corresponding operation activity, a production process is triggered, the data is read from the set point and written to the corresponding indicator, then sent to the data tag of the machine where the temperature is set.

2. Subscribe to Data Tags – Trigger Automation from Shop Floor Layer

   In the second use case, automatic triggers are set in SAP Digital Manufacturing. You can subscribe to data tag changes on the shop floor layer, which means that when a data tag on the shop floor layer changes or remains in a specific status (e.g., while true), the automatic trigger in SAP Digital Manufacturing reacts on that data condition and triggers the production process.

   Example: A data tag, which represents temperature in an oven, is mapped to an indicator in SAP Digital Manufacturing. If the temperature reaches a threshold, an alert is sent to the production supervisor. The logic of sending an alert when the threshold is reached is implemented in the production process. This means that when you have subscribed to a data tag and the data tag changes (i.e, a temperature threshold is reached), an alert is sent.

When configuring a production process design with shop floor integration in SAP Digital Manufacturing, the Design Production Processes application allows you to build action blocks in the process that enable reading and writing indicators.

There are three kinds of indicator action blocks in the Design Production Processes application in SAP Digital Manufacturing:

1. Read/Write Indicator

   This action block allows to read values. In this action block, a single asset and a single indicator must be selected and configured when designing the production process.

2. Read/Write Local Indicators

   This action block allows to read values. Before assigning a shop floor system to an asset, you can save the value temporarily to a local indicator (write) and reuse (read) it later. However, the recommendation would rather be to utilize Local or Global Variables in these use cases going forward.

3. Read/Write Flexible Indicators

   This action block allows to read values and write values from selected indicators through asset, reference name, and structure path. Asset, reference name, and structure path can be specified flexibly as an input parameter to the action block by predefined logic in the production process.

Flexible indicators allow for flexible definition of an asset, reference name, and structure path. This means that, for flexible read/write indicator actions, you might reuse the production process for other machines on your shop floor.

On the other hand, "normal" read/write indicators (not flexible) require hard coding of an asset, shop floor system, and indicator. This means that "normal" read/write indicators (not flexible) require the configuration of every indicator of every single machine.

As indicator actions are defined in the Design Production Processes application, every kind of logic, public API call, or third-party system call can be built around the indicator calls. This allows for maximum flexibility when building shop floor integrated processes.

After finishing a production process design, first assign it to a deployment group and then deploy the design from the deployment group to the runtime environment. This ensures that the deployment is in the control of fewer people and disruption to the production environment can be minimized.

When creating the production process, in the Production Process header, select the "Visible to Production Connector / Plant Connectivity Runtime" configuration to make it available in production connector runtime. All deployments need to be done from SAP Digital Manufacturing to the shop floor layer to have the administration of the automation sequences only from one single source.