Motor Overheat Alarm (Level 3)

What does OH3 mean?

This alarm indicates that the motor's temperature, as monitored by an analog input (H3-09=E), has exceeded the OH3 alarm threshold (1.17V). It serves as an early warning of potential motor overheating, allowing for intervention before a more critical fault occurs that could lead to a drive stop.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Reduce the motor load or operating speed to allow the motor to cool down, if possible, and ensure adequate ventilation.

2. 4

   Inspect the motor's cooling system (e.g., cooling fan, heatsinks) and ensure proper airflow around the motor.

3. 5

   Review L1-03 (Motor Overheat Alarm Operation Selection) to confirm the desired drive response to this alarm.