Reducing Radio Interference from Solar Charge Regulator

Demonstration on Reducing Radio Interference from Solar Charge Regulator. This video shows correct location of suppression capacitors. The method is more effective than using inductive chokes for interference at VHF. (Chokes are effective for HF, such as ham radio bands )

[@stevesmith3556]

Very helpful. I have a victron mppt charge controller. I go to some pretty remote places with my camper. The only thing I can get sometimes is SW and AM. I have my radio inductively coupled with a coil coming off the radio antenna to a CCrane antenna booster. So,it picks up everything! 😊 The only way I can get rid of the noise is to unplug the controller. I've been thinking of different ways to get rid of the RFI. This seems to do the trick😁. Thanks!

[@FurgiePower]

Thanks John for the ideas! Ill give it a go when I gather some of the needed supplies.

[@robertnitschke89]

Just got my Ham licence and your advice is excellent. The rfi is hideous and I used to have to turn off my MPPT . Your cap idea works great and got me out of a hole. I intend to try Toroids as well. Thanks John

[@Jebs-Projects]

Thank You the RFI from my EPEVER solar controller is gone.

[@TABE-O]

Absolute champion. Thankyou!!! What size caps and what type?

[@TheOzembuch]

I'm surprised this video has only 45 likes and 1000 vies, invaluable info. Thank you Sir for making and posting this video. I'm going to try this and see how it works, I've been battling solar charge controller interference for way too long. I also have 3 of them. One quick question , if you see this comment, the ceramic disc capacitor you recommend is not polarized, so it should not matter which way it is installed, am I correct? Thank you again !

[@johnclothier4366]

For PROFESSIONAL remediation of rfi, then everything said here must be done similarly, but more rigorously. For a commercial or military installation, the rfi engineer will totally enclose a rf noisy device, including the filters described here. To achieve near-zero rfi, it is nearly impossible to simply add a filter box EXTERNALLY to the noise-producing device. Also, every input or output line must traverse the enclosure via a feedthru capacitor. In the case of enclosing some digital device having many control lines, one can use a multi-contact receptacle, where each connector pin is also a feedthru capacitor. ...RFI testing of the remedied noisy device is done in an rf shielded room and each wire that enters or leaves the device under test is probed for rfi current using a calibrated receiver, or spectrum analyzer, or at least a scope. ...Regarding the values of the rfi suppression components, these depend on the magnitude of the rfi currents. It is easy to filter DC lines, using large capacitor values. SINGLE-ENDED (single wire) ac signal circuits are difficult because a large shunt capacitance to common may affect the desired signal. In this case, it is necessary to redesign the system to use BALANCED signal lines, which are much less prone to RF interference. As audio engineers well know.

[@rayhill1855]

I'm installing a 50kw stand alone off grid solar system. I wanted to know how, what, and where. I'm looking to cover 80 meters to 10 meters. looks like I need to look else where for the answers.

[@mikedevita5558]

So I should not ground to earth ground either from the device or battery?

[@MrMickrobo]

How would I ground the caps in my Motorhome (RV)? just upgraded my new old MH 300 watts through 20 amp MPPT I am thinking of using a ground spike to improve the signal. Any Thoughts Mike M7 HTO

[@Godshole]

Hello Mr Clothier, I have been trying for some time to find a solution to the exact same problem you have encountered and solved with the same tracer MPPT solar charge controller (the small one) I have set up in my shed to run LED lighting and a car CD/Radio. When the panel is providing power to the controller, in any light it just wipes out the FM radio. My electronics skills are as my dear old Dad would say " enough to be dangerous " ;) However I do understand the basics of the solution you have there apart from becoming utterly bewildered at the choice, type, and variabilities of capacitors available to buy. Would you be kind enough to clarify a few things for me? I think you are suggesting using 0.1 capacitors, but I cannot work out from your video what value they are, pF? nF? uF? While I can see the capacitors I am a bit bewildered by what type they are. They look like the ones that are termed 'polyester' with no polarity, unlike the ones in a tube or cylinder. Is there a particular type that suits the job better? I think I would have to buy capacitors rated above the maximum voltage DC that my set up might encounter. My Tracer-2210RN suggests a limit of 100V input on the solar. So I would think double that or upwards to be safe. I understand that >5% relates to the tolerance, to get a pair that are closely matched. The quality supplier i am looking at (RS components) has many, many such things but the price (which I am happy to pay for the right components ) is a bit steep. The issue is that i want to get the right ones first time and as you suggest adding suppression to the solar input line at the controler, the line to the battery bank at the controler, and I assume to the LOAD line at the controler, at £3 to £5 each cap that is a lot of pennies to get the wrong ones. I would very much appreciate any information you can pass on, and my apologies for my long winded waffling.

[@johnclothier4366]

Hello back to you!. The capacitors can be the very low cost ceramic disc type. Value is 0.01uF. I used those with 50Vdc rating. Because I knew my dc voltages were always less than that. This is a partial solution. Brings the interference on the solar power lines much lower. For very faint FM signals I still had a problem, so I needed to move my FM receiving antenna to the other side of the yard! (The 3-element Yagi antenna was picking up my own solar interference in the FM band even after I had reduced the noise on the POWER lines, and also because I had laid the antenna coax too close to the lines from the solar panels. Note that my problem was only for a very faint FM station carrying my classical music from 50 miles away, over the mountains. There is no interference on the local schlock-rock, junk channels!). The professional solution here would be to enclose the controllers and as much equipment as possible inside a metal cabinet, with bypass capacitors and chokes on all ins and outs. And wiring to the solar panels could be run in metal conduit instead of the usual plastic. When a dc-to-ac inverter is used, it also generates rf interference and it can also be suppressed with 0.01uF caps on the inputs and outputs. Caps on the the 120 or 240Vac output wires will need to be the more expensive plastic film types, rated at 2X line voltage. Again, best results are when all is enclosed in a metal cabinet. With cooling fan! All this is in addition to whatever suppression that the equip manufacturer may or may not have, internally. All above is what a radio amateur might need to do for operation of his sensitive receivers. Not normally necessary for fm or tv.

[@Godshole]

@@johnclothier4366 Thank you ever so much for your prompt and comprehensive reply. Reception is not great where I am and I initially tried moving the ariel as far as I could but even with a battery radio and being half way across the garden the Tracer unit broadcasts for a long long way. By chance my brother in law has sourced a very good metal cabinet recently (faraday cage effect) which I intend to use when I install the gear in its more permanent location. I had already read about using shielded wire to earth for the cables, armoured cable for example and was planning on trying that. I also have some ferrite rings, plus was going to try the twisted pair effect on the existing cables. But as you explain, it will probably still radiate. I can order the right capacitors now and then when I get to the day I tackle it I will have all the options at hand. Thank you again and when I do get to it, which might be a bit yet with it being winter in Scotland I will update you as to what did what as I try each option. It will make for an interesting written addition to your video.

[@pnadk]

Unfortunately you stopped short of giving examples of capacitor values or how to calculate them.

[@johnclothier4366]

Capacitance is not critical. A value of 0.1uf will cure the main problems. ...Please note that this video talks about reducing rfi on DC lines. For the ac side, where a sinewave inverter is sending rfi into a building via the 120/240Vac power wiring, then a familiar cure is to purchase an off the shelf power line filter, installed very near the inverter ac output. Does little good to put said filter in the home....must suppress the rfi at the source...the inverter output. The filter housing must be connected to the inverter housing. That connection will be radiating any rfi, so keep it as short s possible. If the inverter is not a sinewave unit, then you can still use the power line filter to remove radio noise, but the filter will not make the ac output more sinusoidal... the quasi sinewave has a huge percentage of 60Hz harmonics, like 180Hz, etc. These will not be suppressed by the RF filter and will be heard as buzzing in some entertainment systems that are operating from that quasi sinewave. Yet we may have eliminated the much higher frequency rf noise picked up by a communications receiver.