The RFI kit is designed to suppress RFI caused by Solar micro-inverters, power optimizer, and solar arrays by electrically isolating the “antenna” wires used to connect the various devices.The cabling between the PV array, the micro-inverters or power optimizers and their connection to the electrical bus combining their individual outputs can be considered “antennas” for the pulse switching circuits of the individual devices thereby causing radiation at very low fundamental frequencies with harmonics that can cause undesirable radio interference in the 1-30 MHz (and sometimes higher) frequency range.This interference may be objectionable to the owner of the solar installation as well as neighbors who may also experience the interference to their electronic devices.
THE RFI KIT FILTERS ONLY SUPPRESS COMMON MODE CURRENT (SIGNALS) THAT ARE COMMON TO ALL WIRES IN THE CABLE, AND DOES NOT EFFECT INDIVIDUAL DIFFERENTIAL SIGNALS ON EACH WIRE. THE FILTERS HAVE NO EFFECT ON THE NORMAL SIGNALS CARRIED WITHIN THE CABLE.
Power Optimizer RFI
Ferrite cores (slip on) have the two (+/-) cables from the solar array module thru the middle of the core and the two wires hooked to the “string” connecting the optimizers together. Suppressing RFI on all wires in and out of the optimizers helps to reduce any broadband RFI “noise” generated in the SOURCE switching circuits (typically at 200-1000 KHz and harmonics thereof). Two ferrite filters are required for each optimizer – we recommended Part # PV-RFI-PO (includes two ring filters). See typical installation diagram below: