Charger emits a high-pitched whining or buzzing noise during operation.

Safety first: Unusual noises can indicate stress on components. Monitor closely.

• Identify source: Carefully listen to locate whether the noise comes from the contactor, PSU area, or fan.
• Check mounting: Ensure the charger is firmly mounted to a solid wall; loose mounting can amplify vibration.
• Inspect contactor: With power OFF, check that the contactor is securely fastened and not loose in its mount.
• Load test: Note whether the noise changes with charging current. If it increases significantly at high load, have a technician inspect for overheating or component wear.

Mild humming can be normal, but sudden or very loud noise warrants professional inspection.