Motor Overheat Alarm (Level 3)
Yaskawa · E7 Drive
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.
Complete Troubleshooting Guide
- 1
Check the actual motor temperature directly using a thermal gun or an external temperature probe.
- 2
Verify the functionality, calibration, and wiring of the motor temperature sensor connected to the drive's analog input (H3-09).
- 3
Reduce the motor load or operating speed to allow the motor to cool down, if possible, and ensure adequate ventilation.
- 4
Inspect the motor's cooling system (e.g., cooling fan, heatsinks) and ensure proper airflow around the motor.
- 5
Review L1-03 (Motor Overheat Alarm Operation Selection) to confirm the desired drive response to this alarm.