How to Use Fast Commissioning Mode in TIA Portal

A step-by-step guide to working with Fast Commissioning, the new tool for efficiently modifying safety programs in S7-1200F and S7-1500F CPUs available from TIA Portal version 17.

One of the worst parts about working with the integrated safety features of TIA Portal and the S7–1200F/S7–1500F controllers has been the fact that every change to the safety program requires a full compile and download including a PLC STOP. Especially on larger systems, the time required to compile and download can create inefficiencies for engineering and commissioning teams.

In TIA Portal v17, Siemens has introduced a new feature, called Fast Commissioning, that directly addresses this issue. With Fast Commissioning, you can compile the changes to your safety program and download them to a PLC without a PLC STOP.

In the rest of this article, we’ll look at how to enable the Fast Commissioning mode of an S7–1500F CPU as well as the changes that are and are not permitted in Fast Commissioning mode.

Fast Commissioning Demo

Enabling Fast Commissioning Mode

In TIA Portal v17, I have created a new project and added an S7–1511F controller along with local F-DI and F-DQ IO modules.

New Project in TIA Portal v17

In Safety Administration > Settings, I allow disabling of the safety mode of the CPU. You may notice that in TIA Portal v17, there is a time limit for how long the safety mode can be disabled. If the safety mode is disabled for longer than this time limit, then the PLC will STOP and the safety program must be recompiled and downloaded.

Allow Disabling of Safety Mode

With disabling of safety mode enabled, I do a complete download to the PLC. Once the PLC is running again, I go online with the PLC and open the Safety Administration.

In the Safety Administration, I now have the option to disable the safety mode and to activate fast commissioning.

Buttons to disable safety mode/activate fast commissioning mode

To use fast commissioning mode, the safety mode must be disabled. Click the button to disable the safety mode and then click the button to activate fast commissioning mode.

Legal Changes in Fast Commissioning Mode

Now, we can modify the safety program with legal changes and download those changes to the PLC without stopping the PLC. Let’s look at some changes that are legal to make during fast commissioning.

First, I can add a new instruction to a network. In this case, I will add a Normally Open Contact to Network 1 of my Main_Safety_RTG1 block.

Adding a new instruction during fast commissioning

I can also make changes to the interface of a block during fast commissioning. Here, I have added a new static variable s_ESO4_OK and interconnected it with the new Normally Open Contact.

Adding a new static variable during fast commissioning

Finally, I can change function parameters. Here, I change the PT parameter of the TON block from T#5s to T#10s.

Modifying a parameter during fast commissioning

With these changes made, I can download them to the controller. In the Load Preview screen, you can see that this is a “Fast commissioning download”. This indicates that the PLC will not STOP because of the change.

Fast Commissioning download

Illegal Changes in Fast Commissioning Mode

It is not allowed to add a safety timer or any function that uses a safety timer in Fast Commissioning mode. To add these instructions, you will need to disable fast commissioning mode and do a full compile/download.

In this example, I have added a TON instruction to the safety program with fast commissioning enabled.

Add an F-TON instruction

In the Load Preview window, I see that the safety software compilation resulted in an error.

Compilation error

If I look in the compile window, I see that the F-System blocks aren’t compiled because Fast Commissioning is still active.

Compilation failed because fast commissioning is active

Note that it is not only timer functions that cannot be added in Fast Commissioning mode. You cannot add any function that uses a timer (such as the ESTOP1 block) in Fast Commissioning mode.

Other changes which are not permitted in Fast Commissioning include adding hardware and modifying hardware module settings (excluding renaming a tag associated with a safety IO module).

Exiting Fast Commissioning Mode

When you are finished making changes to the safety program, you must exit Fast Commissioning mode.

When you open the Safety Administration, you can see that you have no valid safety signatures after making changes in Fast Commissioning mode.

No Valid F-Signatures

To correct this, you need to deactivate the Fast Commissioning mode with the Deactivate Fast Commissioning button.

Once Fast Commissioning has been deactivated, you can go offline with the PLC and do a full compile and download of the project. When downloading, the PLC is stopped.

After the download, go back online with the PLC and open the Safety Administration. Here you can see that the safety mode is enabled again (since the PLC has stopped and started again) and that the online and offline F-Signatures match.



Fast Commissioning provides an efficient way of modifying a safety PLC while engineering or commissioning the integrated safety. With Fast Commissioning made enabled, you can download legal changes to the safety program without stopping the PLC.

Before deciding if you want to work with fast commissioning mode, you should be aware of the two main limitations;

  1. Not all changes are legal in Fast Commissioning mode. For example, you cannot add any functions that use timers to the safety program in Fast Commissioning mode.
  2. To make the changes made during Fast Commissioning permanent and valid, you must stop the PLC and do a complete download within 8 hours of deactivating the safety mode.

As someone who has been involved in commissioning large safety systems, I think Fast Commissioning is an incredible tool. It addresses the major challenges that we faced during safety commissioning (loss of time due to compile and download time for each change) and will allow our safety teams on future projects to work more quickly and more efficiently.

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