The When you double-click the Meter processor function's configuration , the function’s configuration dialog opens.
In the Meter key field above the settings in the Configuration tab, an automatically created Meter key will be displayed. This key is one of the parameters used when creating meters using the APIs, see API Documentation, and next to the field is a 
Copy button that you can use to copy the key when creating meters.
The Configuration tab contains the following settings:
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The Meter Processor must have at least one guiding rule configured. You can add additional guiding rules by clicking the Add guiding rule 
button at the bottom of the configuration screen. Each guiding rule contains the following settings.
Setting | Description |
|---|---|
Guiding rule | |
Name | Enter an intuitive name for the guidling guiding rule in this field. |
Condition setting | Select if you want to define customized conditions for the rule or not by selecting either No conditon or Custom condition. If you select No condition, nothing more is required, but if you select Custom condition, a new section called Condition n will appear , and when you expand it, it looks like thisthat you can expand and enter any conditions you want to be met for the usage to be counted:  You can configure additional conditions by clicking on the Add condition button at the bottom of this section, and if you have more than one condition, you can select to have either AND as a separator or OR, but not a combination of the two. Each condition is configured with three settings:
For example: Field: Location The name of the condition will now be converted to show your configuration which will make it easier to see what conditions are set even after collapsing the conditions:  |
Category to match | Select which category you want to count usage for in this drop-down. The Meter Processor is referring to categories instead of individual Meter Types which provides you with the possibility to add, remove, or update Meter Types whithout having to update the configuration of the Meter Processor. All existing categories configured in Meter Types will be displayed, see Creating Meter Types. |
Group by | |
Group by n | If you want to group the usage based on a specific field, for example region, click on the Add group by button to display a Group by n drop-down.  In this drop-down-list you can select the field(s) you want to group the usage by. You can either select an existing field or create a new field by entering a new field in the Add Field field and clicking on the + button. You can enter several fields for each Group by n, but it is not recommended to have more than 2 Group by n configured. |
Other operations | |
If you want to perform other operations, you can click on the Add operation button to display a section for defining operations that you want to be made:  | |
Operation | Select which type of operation you want to perform:
|
Field | Select the field you want to perform the Carry first or Carry last operation on. You can either select an existing field or create a new field by entering a new field in the Add Field field and clicking on the + button. |