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

Safety first: Noise often comes from live components; do not touch internal parts while energized.

• Identify source: With the cover on, listen carefully to locate whether the noise comes from the top, bottom, or side of the unit.
• Check for vibration: Ensure the charger is firmly mounted to a solid wall. Tighten mounting screws to reduce resonance.
• Inspect contactor: With power off and cover removed, check that the main contactor is securely fastened and that no mounting screws are loose.
• Look for damage: If the contactor shows signs of overheating or mechanical wear, plan to replace it or the entire power module.
• Test under load: After reassembly, observe whether noise increases with current. Persistent loud buzzing usually indicates a failing contactor that should be replaced.