Some noise from an operating inverter is normal, because turning DC into AC always makes some sound, and datasheets give a typical noise level for each model. Fan noise goes up and down with power and internal heat, so the inverter is louder at midday and quieter in the morning or in cold weather. If the status lights are green and no error is shown, this is normal. Clicking or pulsing sounds during grid impedance measurement are also normal. Mounting the inverter on a solid wall rather than plasterboard or wood keeps the volume down. Buzzing from the backup contactor after backup is switched on can sometimes be cleared by switching the AC fuse off and on again so the contactor re-seats. If the customer does not use backup, you can turn the function off instead. Rattling or snarling that continues with backup turned off may be a cable touching the internal fan, and the source says the inverter must then be replaced. Buzzing from the power stage has been fixed by firmware updates on some models, so check the inverter's firmware version and the release notes. Noise heard on radio receivers is radio frequency interference, which is a separate issue. Measure the noise at different distances from the inverter and its cables to find the source.
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observed_asc1 verified · fact Abnormal fan noise
Rattling or snarling noise that continues with backup mode disabled can come from a cable touching the internal fan; the source says the inverter must then be replaced.
sec=h1 h=dd39c63b2d2fverified by: review-workflowverified on: 2026-10-24
c2 verified · fact Contactor buzzing noise proposed
Buzzing from the backup contactor after the backup function is activated, loud enough to be heard elsewhere in the house.
sec=h1 h=dd39c63b2d2fverified by: review-workflowverified on: 2026-10-24
c3 drafted · lead Grid impedance measurement noise proposed
Clicking or cyclic pulsing noise while the inverter measures grid impedance. This is normal behaviour, and the volume depends on the power fed in and on hardware such as chokes.
sec=h1 h=ba0e0c7ab062review note: support check: partial - Clicking and cyclic pulsing during grid impedance measurement, with volume depending on power fed in and hardware like chokes, are stated, but only clicking is called normal; the pulse is described as audible, not explicitly normal.; review: partial - The SMA passage confirms clicking and an audible cyclic current pulse during grid impedance measurement, and says volume depends on power fed in and hardware such as chokes, but it calls only the clicking normal, while the note calls both…
c4 verified · fact Power-correlated noise level proposed
Fan and audible level rise and fall with power throughput and internal temperature: louder at midday, quieter in the morning, evening or on cold days. This is normal unless an error is shown.
sec=h3 h=82129b1df69bverified by: review-workflowverified on: 2026-10-24
presents_as c11