Chapter 12: Managing Navigation and Alarms

This chapter focuses on how to create navigation between pages in TIA Portal's Unified HMI environment and how to create an alarm management system between the HMI and PLC.

Navigation is important in the HMI, and it is something that an end user interacts with often. There are different styles and approaches to navigation. Alarming is also important as that's how an end user is notified of potential issues. Methods for alarming can also be achieved in many different ways.

In this chapter, the following topics will be explored:

• HMI navigation
• HMI alarm controls
• Alarm tags – accepting and resetting
• PLC-driven alarming

HMI navigation

In order to change pages on the HMI so that more than one page of information can be displayed, a navigation system is required.

TIA Portal offers a standard approach to managing page navigation that is both simple and easy to utilize. Depending on the application requirements, pages can be configured in multiple ways, such as free navigation or controlled navigation:

• Free navigation is a method where every page has a navigation link to every other page:

Figure 12.1 – An example of free navigation

• Controlled navigation is a method where page access is controlled via the current page. This allows the segregation of settings pages, for example:

Figure 12.2 – An example of controlled navigation

Free and controlled navigation styles can be mixed also, whereby some pages are accessible at all locations, and some are controlled and can only be accessed in key locations. Mixing navigation...

HMI alarm controls

One of the main reasons for an HMI to be included in a project is so that alarms can be relayed to an operator or end user. TIA Portal has a ready-made control for alarm management called the alarm control:

Figure 12.7 – An example of an alarm control on a screen with the alarm control object in the toolbox on the right-hand side

The Alarm control option can be found in the Controls section of the toolbox. Alarm control can simply be dragged and dropped onto a screen as with any other object.

Alarm control connects to many different areas and has many different configuration options for customizability. In most cases, for a quick setup, the preset options are enough to display and interact with alarms.

Note

The HMI used in this chapter is an MTP1500, running V17 Firmware.

Configuration of HMI alarms

In the Project tree and under the HMI object, an object called HMI alarms exists. It is within HMI alarms that the alarm...

Alarm tags

In the PLC, dedicated tags or data block addresses are required to be used in order to tell the HMI that an alarm has been raised. These exist in the HMI as the trigger tag and acknowledgment status tag.

Logic is developed against these tags in order to react to operator acknowledgment of alarms and to raise the instance of the alarm. Figure 12.19 shows a basic example of ladder logic controlling a latching interlock:

Figure 12.20 – An example of a basic alarm interface

When Scaled_Value for Instrument_1 is above High_Alarm_Trigger, both the trigger tag ("Alarms".Alarm_Group_1.Active[0].%X0) and High_Interlock are set to True. When this occurs, the HMI writes to the acknowledgment status tag ("Alarms".Alarm_Group_1.Accepted[0].%X0) and sets it to False, which then holds on to the trigger tag:

Figure 12.21 – A latched alarm in the HMI

If the trigger tag returns to a False value, the acknowledgment...

PLC-driven alarming

When a PLC and an HMI exist in the same project, common alarm classes can be configured for use in both devices.

Using supervisions and the ProDiag function block, the PLC can drive alarms to the HMI without having to configure HMI alarms in the HMI itself. One of the biggest benefits of using PLC-driven alarming is that the alarm resides in the function block associated with a supervision. This means that if the function block is standardized in a library, every project that uses the function block will be able to generate the same alarm automatically.

Supervisions can easily be created for any variable that is stored in a data block or as a PLC tag:

Figure 12.23 – Creating a supervision

In the Supervision column, right-click and choose Add new supervision. The properties window at the bottom of the screen opens on the Supervisions tab.

Note

TIA Portal will automatically create a global ProDiag function block and an associated...

Summary

This chapter has explored essential areas of HMI navigation and alarming. These aspects of HMI development are key to providing information to the end user and building a robust and easy-to-use system. Being able to create easy-to-use navigation systems and clear alarming systems can set a project apart from others, ensuring that end users have an easy experience when the overall system is in use.

Using PLC-driven alarming via the supervision tags can help reduce the amount of work required in the HMI by allowing the PLC to interact directly with the HMI's alarm control. The utilization of PLC-driven alarming ensures that function blocks will raise the same alarms no matter what project they are used in (subject to ProDiag supervisions being available), which can have large time-saving benefits as well as standardization.

Supervision tags use the ProDiag system that requires an additional license after the configuration of 25 supervisions. The license can be set...