Charger makes loud buzzing, humming, or clicking noises during operation.

Note: Some low-level hum is normal, but loud or new noises indicate a problem.

• Identify source: With the cover on, listen carefully to locate whether the noise comes from the top, bottom, or side of the charger.
• Check for vibration: Ensure the ABB charger is firmly mounted to the wall and that mounting screws are tight.
• Inspect fan: If the noise varies with fan speed, the internal cooling fan may have worn bearings and should be replaced.
• Internal check (technician): A technician should verify that the main contactor is securely mounted and not chattering due to control issues, and inspect inductors/transformers for loose laminations.
• Replace noisy components: Replace the fan, contactor, or power module if they are the confirmed source of abnormal noise.