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SnowDrifter

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Everything posted by SnowDrifter

  1. External regulator. Turn a dial to set the voltage and you're done. Alternator is PCM controlled and adjusted from measurements taken from a ground clamp IIRC.
  2. Might try shooting them an email for that one I can speak to chemistry and usability. But I don't have any hands on experience with the things and am hesitant to make any recommendations given the financial cost of these units
  3. IMO.... LiFePO4 is more suited for bulk storage. Such as parking your car at a show and playing it with the engine off for extended periods. These batteries (like all batteries) have a cycle count before they degrade and become inappropriate for use. With good care, you should be in the 1200-2000 cycle count range. XS power uses LTO (Lithium Titanate) in their titan8 products (yinglong IIRC) - this has a lower energy density than lithium iron phosphate, but can tolerate a much higher current load. This chemistry, while expensive and bulky for the storage you get, tolerates a far, FAR higher cycle count than other lithium chemistries - nearly on par with capacitors. LTO cells should be somewhere around the 20k cycle count range. They're also a bit more temperature tolerant than LiFePO4 / NMC / NCA chemistries. With that background, if you're looking for a daily groundpounder, I'd submit that LTO is the most suited for this task. Bit pricier and bulkier for a given capacity, but lower resistance, high cycle count, and temperature tolerance allows for a more straightforward install. Independent of which choice you get: You'll want to use an externally regulated alternator, and remove any lead/acid batteries you have. Current automotive alternators are intended to operate around a lead/acid chemistry (charge at higher voltage when cold for bulk charge, then taper off to lower voltage) that are NOT suited for lithium cells (constant current / constant voltage). And be mindful not to overcharge the things. You can get away with pushing voltages on lead / acid batteries. If you do the same with lithium: Best case, you chop your product lifetime to a fraction of what it would otherwise be. Worst case: you ever seen a lithium fire? They're nasty. If you want to DIY, read heavily into balancers, BMS systems, lithium charge profiles, and charge/discharge ratings. If you buy off-the-shelf from XS power or something - read the spec sheet and adhere to it.
  4. Clipping refers to the tips of the sine wave literally being 'clipped' off because the signal/gain is being driven beyond what the power supply / voltage of the amplifier can supply Bottoming out is a different issue altogether. Too much power, too big of a box, too little port, playing below tuning, etc. In either scenario: The reason for the extra heat is because in clipping, you're now sending DC voltage to a system designed for AC voltage. A current moving through a wire creates a magnetic field, and a wire moving through a magnetic field creates current. Your speaker is a wire moving through a magnetic field, and there's some interplay between those two properties. This is called inductance - it's why you have a DC resistance of the coils. But if you so much as breathe on it, you'll get wildly fluctuating readings. That's also the property that is responsible for 'rise' - or the frequency dependent variation in AC resistance presented by a particular driver/install. Here's a graphic from the IM-SG owner's manual for clarification on what that looks like Pushing beyond mechanical specification results in a similar behavior because the coil is leaving the magnetic field and becoming a simple resistor. No inductive feedback = more power than intended is being sent.
  5. Clipping is an electrical property, not mechanical. It refers to the voltage profile going to your driver
  6. Dude we aren't google. We are people. Please speak to us accordingly.

  7. Unfortuntaly this can be an issue on some larger alternators. Part of why we as a forum generally recommend some pretty specific alternator brands. Mechman, DC. I believe Singer's turned a corner in the last couple years, but I have no experience with them. Raising your idle is definitely a thing. Might be able to be done through software - trying to tighten a throttle cable or something will make you sad. Just... Don't.... For my old vehicle, I was cramming 20lbs into a 10lb bag and got a 390a alternator. The engine had a 5.5" crank pulley on it which was below turnon speed for the alt. But... I knew what I was getting into. The finals solution to that one was to get a custom 7.5" overdrive crank pulley tooled up from a company called Unorthodox Racing. Also got a couple extra ribs on there and associated power steering pulley for belt slip. Wasn't the easiest, or cheapest solution, but IMO, was the most elegant as I had no room for dual alts or similar. IIRC, was around $800 ish. Cost more than the alt, but it got me to where I needed to be. Not sure how much you paid for your unit or what your other restrictions are. But, realistically, you have 3 options 1. Different alt / send to manufacturer for better idle output 2. Overdrive pulley on the crank. You really won't be able to get a smaller than 1.75" pulley for the alt. And if you somehow manage to, it'll slip. A lot. 3. Program a higher idle speed in the computer (touch base w/ your local race / dyno shop)
  8. Built a wheel that won't kill me. Last one was pretty irreparablebly dickered. First time doing anything like it. Wasn't too bad tbh, just need to be methodical and patient. 3sp internal gearing, plus 9sp wide range cassette. That was the final step, now it's officially done. Final result is an ace of spades, king of none that will comfortably do forest trails and street use. Usable speed range from 2 to 35mph with comfortable pedaling. Only other bit is a stronger fork... But ill tackle that if or when any issues present themselves. Shits expensive at the moment
  9. Wouldn't even say for the win. They're just different beasts altogether. To SUPER simplify it: LiFePO4 is closer to a battery (energy density nearly double LTO) LTO is closer to a capacitor - high draw / high charge capabilities, ridiculously high cycle count. I avoided making any product recommendations... But tbh, for car audio beating, I'd probably veer to LTO if costs and space allow. IMO, it's a bit more suited for handling the high draw / high charge demands and cycle counts associated with our applications. Should see a better product lifetime. This is, assuming, you'll be playing with the car on. If you want to park at a show, go engine off, and beat on the thing for an hour or 2, then I'd just toss together an 800+ah LiFePO4 bank. Else, LTO go brrrr Some edits as I'm still waking up: But this assumes equal opportunity to both product varieties. It sounds like OP has good access to LiFePO4 cells which presents a pretty compelling cost argument. 128ah lithium iron phosphate battery for 700 bucks? Dude, you'd have to be insane to stick your nose up at that. Do it. DO IT. Also, that key word... Build... Please, PLEASE get familiar with lithium chemistry and pitfalls. Use an externally regulated alt. Do NOT EVER over charge them. Use a BMS - make sure cells are balanced. You'll get good lifetime out of the things if you go easy on charging and stop short of full charge voltage - 80-90% SOC, as opposed to 100. If you're in a cold climate, insulate the things. Maybe install a heater in the pack so they don't freeze. Don't forget ventilation for the hot months as heat realllllly reduces lifetime of these things. Feel free to post back here or DM me if you have questions on this stuff. I have a fair bit of experience tinkering with the stuff. I was dicking around with lithium before it was cool lmao Also, Dafaseles, love you buddy, but I think you jumbled some info on your assessment
  10. https://www.digikey.com/en/products/detail/onsemi/BAT54CLT1G/1748976 ?
  11. Lithium Iron Phosphate (LiFePO4) - higher energy density, lower cost/wh, wider assortment of form factors. Nominal voltage of 3.3vpc, with cutoff/termination voltages at 2.5/3.6v. Lithium Titanate (LTO) - lower energy density, bulkier, higher cost/wh. Will accept tremendously high charge/discharge loads relative to their capacity. Very high cycle count. Form factors are limited. Nominal voltage of 2.3vpc, with cutoff/termination voltages at 1.5/2.8v.
  12. Are you designing from the ground up? Or going from a kit? There are pre made plans out there. Print parts, assemble, and go. Voron, ratrig, hypercube, railcore. For endstops: I prefer mechanical Though for your Z axis, you might be better off with a bltouch or similar as that'll let you do offsets and bed leveling without having to dick around with 4 corners and paper. Little hard to judge other bits without specific info. Like... Why are you doing 4 PCB heaters as opposed to one from keenovo? Will a 240w PSU keep up with that? etc Open offer: If you need any 3d printed brackets or whatever for assembly, HMU and we can work something out. I can print anything short of PEI parts on my end. Can to PEEK / PEKK, but only small stuff.
  13. Not nearly as bright as you'd think... Maybe 1500 lumens or so for the pair, which, tbh, is *just right* for me
  14. Power is V^2/R. An increase in voltage is also associated with an increase in amperage, which exponentially affects power. Think of it like water pressure: If you double the water pressure coming out of a hose, you'll also get more flow at that higher pressure. Simpler way, that takes into account manufacturing error of the amplifier: Note: Use this only if you don't have access to an oscope/dd-1. It's very dirty.. But better than doing it by some other arbitrary metric, or by doing spreadsheets (especially if the amp in question is over-rated) 1. Play a square wave at max gain (please disconnect your drivers). This will measure the peak to peak voltage of your amp - i.e. the rail voltage. Let's say... You measure 60v. 2. Turn everything down/off. Take that number you just got, and convert to RMS voltage by dividing by sqrt(2). So you'd take 60v/sqrt(2) = 42v 3. Play a sine wave at your desired amplitude (say -5db) and turn the gain up on your amp until your output voltage is 42v. Don't get excited and go higher - that's just clipping. 4. Hook your equipment back up
  15. Put some lights on the bike and wired right to the battery. Hated dicking around with rechargeable schitt. Funny thing is: These were 27 bucks.... The rechargable handlebar mount thing I had on there before was 55... Also a MUCH needed brake upgrade thanks to a VERY good friend. The OG brakes sort of.... Ate the dust yesterday
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