Cause: IGBT thermal state comes when one or more Insulated Gate Bipolar Transistors (IGBTs) within the drive are operating at a dangerously high temperature.  The drive is being pushed beyond its rated capacity, causing excessive current flow and heat generation in the IGBTs.

"tJA" warning in Schneider ATV950 drive IGBT thermal state condition. This means the Insulated Gate Bipolar Transistor (IGBT) module, which is a critical component in the drive's power stage, is experiencing a thermal condition that could lead to overheating. IGBTs are used for switching and controlling the power to the motor, and excessive temperatures can affect their performance and longevity.

Here are steps to address the tJA warning:

1. Check Ambient Temperature:

   • Ensure that the ambient temperature around the drive is within the specified operating range. Excessive ambient heat can contribute to the IGBT’s internal temperature rising.

2. Verify Cooling and Ventilation:

   • Make sure the drive’s cooling system is functioning properly. Check for any blockages in the cooling vents and clean any dust or debris that might be obstructing airflow.
   • Ensure that the cooling fan is operational. Listen for unusual noises that might indicate a failing fan.

3. Inspect Installation Environment:

   • Ensure that the drive is installed in a well-ventilated area with adequate space around it for proper airflow.
   • Avoid placing the drive near other heat-generating equipment that could increase the ambient temperature.

4. Check for Overload Conditions:

   • Verify that the drive is not being overloaded. Excessive load can cause the IGBTs to overheat. Ensure that the load is within the drive’s rated capacity.
   • Monitor the current draw of the motor and ensure it is within acceptable limits.

5. Review Drive Configuration:

   • Check the drive’s configuration settings to ensure they are appropriate for the application. Incorrect settings, such as too high a current limit or improper motor parameters, can cause excessive heat generation.

6. Monitor IGBT Temperature:

   • Use the drive’s monitoring features to observe the real-time temperature of the IGBT module. Look for patterns or specific conditions that might be causing the temperature to rise.

7. Inspect Electrical Connections:

   • Ensure that all electrical connections to the drive are secure and free from corrosion. Poor connections can lead to increased resistance and heat generation.