Here’s a good article to get you started. https://www.fluke.com/en-us/learn/blog/power-quality/electrical-noise-and-transients
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Yeah you will have to keep investigating to find the cause,
One time I had a funky problem similar to that but not identical… turned out the 5V and Gnd wires were fine but the Signal wire on the PWM (“PPM”) going to the radio receiver was broken and barely touching.
And one time I had a radio receiver for the Mini that just acted weird … just didn’t use that receiver again, problems disappear.
Keep swapping things one at a time until you find the root cause. Until you know what caused it, don’t stop looking, because it’s a safety hazard. Maybe ride with those lights off for an entire week (carry a handheld light) and see if it ever happens, then ride with them on for a whole week, even during the day, and see… just keep testing…
I have a noob question 
When I connect the step down converter (12V/60W) to the battery it bangs and sparks. Is this normal? Never heard about this issue or the need of anti-spark solutions. Furthermore the LED’s make a buzzing noise which they don’t do when connected to li-ion 3s1p.
Any ideas? 
Yes, the bigger the battery the bigger spark… I have a switch wired to the ground from my battery line to the converter input…
Most converters will draw some sort of power even when not in use so you want to make it powers off as well when lighting isnt needed
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Thanks, 12s6p BTW
That was my plan, too but then there is always a spark when switching on, right? 
Yes, my DC/DC converters do that too, but not nearly as bad as a typical ESC
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If so not noticeable, and after 100s of switch throws for basic lighting setups never haf a switch failure or anything
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I mean it def spunds like the new converter as this problem only appered when it did… And when its off no issue… On = problems…
And based on @MysticalDork feedback and the article I mean… I wonder if current draw has any relativity… May try and un hook the cobs and see if just the tail light on changes anything…
Also based on the article sounds like potential noise or RFI. Since everything pulls of the battery… Convert, vesc, receiver I assume if it is noise theres.no workaround aside.from a filter as you mentioned OR another power source…
The only other potential option that came to mind would be to power the converter off of the BMS discharge. Since I’m only running a charge only bms because it can only output 15 amps Max there is definite potential there to power a converter off of that … do you think using the BMS would limit any noise?
No, that probably won’t help noticeably. The noise will just go back through the BMS and then through everything else like before.
DC-DC converters work by turning the power on and off very fast through a coil with a switching transistor, and every time the power is on, you get a little voltage dip, and every time the power turns off, you get a voltage spike. That’s the simple explanation of the noise. There are a bunch of more complicated and mathy things going on, but that’s a start. A lost of that noise goes back up the power wires and into anything else connected to them, and some gets radiated out as radio signals and magnetic fields, where it can affect things that aren’t directly connected.
Big, powerful converters from overseas generally don’t have very much in the way of filtering onboard, so they can be particularly noisy, especially at high load.
More expensive converters from more regulated sources tend to have better noise filtering built in, or at least show recommendations in their datasheets/application notes about how best to set up your own filter. (They also often have the added advantage of being more efficient and smaller too! I found a 12v/3A converter with 90+% efficiency on Mouser that’s about 1.5" square and 0.5" tall. Very very compact.)
I.appreciate all the info and help… And there’s no easy solution for noise…if it is noise like these?
I know these are more car audio but anything comparable given our application?
There are off-the-shelf noise filters available and they can help, but there are a lot of different types and variations of noise, and some filters are more effective at some types than others. Also the commercial ones tend to be pretty large, especially the really effective ones.
What are the chances this converter is just a fluke? Like an extra noisy one? Maybe I shpuld order another just to see?
You can try, but I wouldn’t bet on it. Better to put that cash towards either a different one, or some filtering mojo.
I know from building my remotes a few capacitors on your receivers 5v can go along way to eliminating dropouts with even with these new maytechs.
There the same thing cob stands for CHIP ON BOARD led tape is a long narrow flexible board with LED chips. I’m presuming your cobs are diodes in a different form from the SMD you often get on most led tapes
Maybe you can use 3 small variable buck converter PCB set the lvls that look balanced
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PWM regulators switch on and of very quickly to lower the voltage/current this causes power spikes and emp. The higher quality electronics try to smother this out. I emphasise the TRY some times it’s not a issue some times a certain combination escalates the issue.
Radio waves are very vulnerable to these effects
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I wire my converter behind the antispark to prevent that. The draw is minimal. >9mA during use (I expect that), when the lights are switched off. (Converter runs 6mA standby current)
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To put it into perspective, that’s losing 6mAh per hour — so for an example battery with a 2 hour range that’s cutting your capacity from something in the neighborhood of 25000mAh to “only” 24988mAh
I’m in the neighborhood of 24Ah. I have a range of about 45km roughly.
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I ordered the only other 2 options on Amazon that were within my max did specs… Will see if anything changes…
Its possible as there space in each segment of my case… My concern is that they’d still blow like the original one… But then again who knows… 1 dedicated per cob would be low draw and maybe that in turn would be of benefit…