> For the complete documentation index, see [llms.txt](https://help.auxalia.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.auxalia.com/plant-tools/plantexpresstools/how-to-use/renumber/usage/use-case-class-related.md).

# Use Case Class Related

This chapter describes how the option **Class Related** is used. We will just show the use case of the **Override** mode. **Fill Gaps** behaves the same way as shown under [Use Case All Types](/plant-tools/plantexpresstools/how-to-use/renumber/usage/use-case-all-types.md).

**Class Related** means, that the value is searched within the class of the selected symbol.

We start with this setting.

![](/files/a109AbpFXbkyBs156yEG)

We use the same example as in the chapter before.

![](/files/PQQGL42AnFNEksHhcRyS)

You can select the symbols from in this order...

![](/files/H8lD61Tro6zr6cj6JTkj)

... or in that order. The result is the same. The values will be given for each class independently. Since all Blowers are from the same class the will get 001 to 003. The same for the Crusher and the Heat Exchanger.

![](/files/yq1jlUCrJjrmro2gNX0Z)

Now let's have a look at this example where we have three valves but from different classes.

![](/files/kaT8nSnywxy6bjM4pXQ2)

If we renumber them, they all get 001 (which of course leads to Tag conflicts). They all get 001, because for each class the value will start at 1.

![](/files/CH4mJtjsnNWFPuU9Vdh7)

There may not be much use cases for this example. At least when renumbering the number of the Tag.