Observation Attribute Analyzers monitor the data payload attached to observations from connected devices. Values like battery level, temperature, altitude, or speed. When a value crosses a threshold you define, EarthRanger automatically creates an Event in the Events Feed so your team can act on it.

This article explains how to create and configure an Observation Attribute Analyzer in the EarthRanger Admin panel.

Prerequisites

• Access to the EarthRanger Admin panel
• At least one Subject Group configured with connected devices that report observation attributes, if you haven’t assigned a Subject Group connected to a device please review (link to source provider configuration) 

Setting Up an Observation Attribute Analyzer

1. In the EarthRanger Admin panel, go to:
     Home > Analyzers > Observation Attribute Analyzers
2. Click Add Observation Attribute Analyzer.
3. Enter an Analyzer Name. This should be unique and descriptive enough to identify it later (e.g., "Low battery — collar fleet").
4. Select the Subject Group this analyzer applies to. The analyzer will only monitor observations from subjects within this group.
5. Leave Active checked to enable the analyzer immediately. To pause the analyzer without deleting it, uncheck this box.
6. Enter the Attribute Name — the exact key of the observation attribute you want to monitor. This must match the key as it appears in the observation data (e.g., battery_level, temperature, tag_voltage).
7. To find the available attribute keys for a subject:
   1. In the Admin panel, open the subject you want to monitor.
   2. At the bottom of the subject page, click “See more observations for this subject here.”
   3. Click on the recorded time of any individual observation to open it.
   4. At the bottom of the observation page, you will find a JSON block containing the additional data for that observation. The keys in that block (e.g., "battery", "speed", "tag_voltage") are the attribute names available for use in the analyzer.
8. Set the Aggregation method. This determines how multiple observation values are combined before being compared against your threshold. 
9. Set the Comparator — the operator used to compare the aggregated value against your threshold. Available options:
10. Set a Warning Value, a Critical Value, or both.
    - Warning Value: triggers a warning-level event when the observed value meets the comparator condition.
    - Critical Value: triggers a critical-level event when the observed value meets the comparator condition.
11. Save. 
    The analyzer will begin monitoring incoming observations for the defined subject group and generate events in the EarthRanger events feed when thresholds are crossed.
    
     

Once saved, the analyzer runs continuously against incoming observations for the selected subject group. Events appear in the EarthRanger events feed as they are generated. To monitor the same attribute across multiple subject groups, create a separate analyzer for each. To temporarily pause an analyzer, uncheck Active rather than deleting the record.