Re: Radio Noise from PV System
Posted my main reply @ OB site ...
The XW will probablly be better than doing filtering outside the CC chassis, but, still, RFI filtering is expensive, and MFGs usually target a certain spec as the limit of amount of filtering applied. Am sure that you can add external filtering to the FM which will exceed that of the XW box. I have NO experience with the XW, BUT, as you noted, Class B levels are still quite a large signal. The noises that you see are, almost certainly Line-Conducted from the CC (both on the input and output leads -- the input leads are usually much longer, and external to the power room, so are most important.
As noted in my other post, isolation of antennas from power generating areas (and to a certain extent power use areas), shielding the conductors to/from PVs (in pipe), filter in/out of CC, filter Inverter outpt, and bury/shield the AC output and so on are the most direct approaches to reducing emissions.
If it is possible to isolate your low-band antennas from the power room/PV array this should make a large difference. It is probable that the Solar has come along after you have built your antenna farm, so this isolation may not be easy or desirable -- do not know if you are off-grid, but with the number of panels noted, you are prob on-grid.
With all the shielding/filtering on the PV side, still, the low-band antennas will probably be affected by the CC emissions, due to their large capture area, and because the solar array is not shielded, and it is not really at all easy to shield them, so keeping the low-band antennas away from the PV/power room will be a large help. Also, filters usually become most effective at higher frequencies.
In my station, I realize that if I must, I can simply switch off the PV in breaker to eliminate the noise, AND, the most important low-band activitity occurrs at a point of low/no PV power input, so the CC might be sleeping anyway.
As noted elsewhere, when the CC is tamed, you will probably discover the Inverter birdies, which may need to be filtered with common-mode filters, LP filter, or perhaps, Ultra Isolation 60 Hz transformers.
Please see the post on the OB site. 73 Ed, and Good Luck, Vic K6IC
Last edited by Vic; September 14th, 2009 at 9:45 PDT.
Off-Grid, Sys1: 1280 AH 48 V bat, 3.150 KW STC PV, MX-60, Xantrex Stacked SW+ 5548s; EU6500isa, 21KW Kubota diesel gens, misc Honda Eu gens
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