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Solar inverter causing radio, TV or WiFi interference: causes and fix

Since installing solar, your FM radio has noise and WiFi drops. It's inverter electromagnetic interference. How to identify and filter.

Published on 2026-05-153 min read

The inverter converts DC to AC with high-frequency switching (15-100 kHz). Inevitably emits electromagnetic interference (EMI). How to detect and reduce.

Typical symptoms

1) FM/AM radio noise when panels produce. 2) Digital TV with image artifacts or audio cuts. 3) WiFi continuous drops if router is nearby. 4) IR remote with low sensitivity.

Confirm it's the inverter

Turn off the inverter DC switch for an hour. Problems disappear: it's the inverter. Turn it back on, wait 1 minute: problems return = confirmed.

Cause: poorly certified inverter

Cheap Chinese inverters meet paper FCC but not real EN 61000-6-3. Tier 1 (Fronius, Victron, Huawei): minimal EMI. Low-cost brands: can be problematic.

Fix: EMI filter

Domestic EMI filter ($60-180) between inverter and AC panel. Reduces 80-90% of conducted EMI. Brands: Schaffner, Schurter, EPCOS. Specific to PV.

Relocate antennas and router

Minimum 10 ft between inverter and WiFi router/TV antenna. If not possible: AC cable shielding with grounded metal mesh. Ethernet instead of WiFi for nearby devices.

Claim to installer

Excessive EMI is a covered warranty defect. Claim to installer or distributor. Inverter fails FCC: free RMA. Serious brand: usually replaces without issue.