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esaj last won the day on May 11

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About esaj

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  1. At least the old King Song "green app" would say "Keep cycling for XX km" to show how many kilometers the battery should still last with current charge. It was just an estimation and not really accurate, but it might be what you're seeing:
  2. Even if they have 100+ previous configurations/firmware modifications, that's not a reason not to make the firmware OTA-upgradeable for the future models. The old ones wouldn't support the upgrade anyway. Saying that they "can't do this because there's so many revisions out there" is a moot point, basically they're just saying that they don't want to manage and track their production at the level required. I write vehicular ECU-bootloaders nowadays for living, it's not really super complicated to do. What is complicated, is the "tracking" of a vehicle life-cycle, with all the "birth certificates" (what ECUs / other hardware components & revisions / firmwares etc the vehicle contains at manufacturing date) and maintenance / repair tracking (firmware updates, replaced components etc). It certainly adds up to the time and cost of production & maintenance. "Some modern motor vehicles have up to 80 ECUs. Embedded software in ECUs continues to increase in line count, complexity, and sophistication.[2] Managing the increasing complexity and number of ECUs in a vehicle has become a key challenge for original equipment manufacturers (OEMs)." https://en.wikipedia.org/wiki/Electronic_control_unit But wheels have only one MCU (MicroController Unit, I guess if stretching the definitions, the entire mainboard could be called an "ECU") running a single piece of firmware. It should be much, much simpler, if they just keep good track of what board revisions, peripheral devices (BT-audio, lights etc), motor and firmware revisions are there in model XYZ, along with proper version "stamping" (hardware and software) so that the bootloader knows to reject incompatible firmware as a failsafe, and can tell the "programming device" (ie. an app in a mobile phone for wheels) the hardware & software configuration of the wheel, so that the app knows to fetch the compatible firmware version. It's not even complicated to make it possible to update the bootloader itself (which is actually required in ECUs) through the same software and communication method which is used for updating the firmware itself, ie. without any special-purpose programming device that would need to be shipped back and forth between reseller and manufacturer, or separately purchased by the reseller. Whether it happens over-the-air with Bluetooth or over CAN-bus, doesn't really make much of a difference from the the functional standpoint.
  3. Check that your multimeter probes are connected correctly (current vs. voltage measurement) before measuring. The power spike before the BMS cuts the power / meter fuse blows is enough to vaporize your probes if you plug them in the battery connector with the meter set up for current measuring... guess how I know? Acetone can be used to "weld" plastic, it liquifies the plastic, which then hardens again once the acetone evaporates. Use small amounts at a time and be careful, the plastic starts to melt pretty quickly. Also inhaling the fumes a lot isn't exactly healthy, so good ventilation isn't a bad idea. Never had more than a slight headache though Mixing plastic (such as Lego-blocks, which are ABS, or something like 3d-printer filaments probably would work nicely too) with acetone creates a "slurry" which can be used to fill in small holes or cracks, or create new threads for screws in plastic (fill the hole to re-thread with the slurry, insert the screw, maybe move it a little bit up and down to ensure the liquid plastic settles in the threads and leave it there until the acetone has evaporated and the plastic has hardened). Easiest way to make small amounts is to take a small glass jar (preferably with a lid), pour some acetone in there and drop the blocks or 3d-printer filament or whatever there, close the lid and swish it around for some time until it has even consistency (the time it takes depends on plastic, sizes of blocks, amount and purity of acetone... if you just leave it sitting it will take a long time, but twirling it around makes it much faster). More acetone vs. plastic makes it more runny and vice versa. Somebody with more understanding of chemistry once said that using solvent-based "gluing" is far superior to "normal" glues, because the bonds occur at molecular levels, ie. basically the parts melt together instead of being held together by a layer of other substance. Draining the caps is a good idea before touching anything on the mainboard, probably pressing the power button is enough, or just place a small resistor across the cap legs and wait a bit (careful not to short anything else with the resistor legs!). But when plugging back in, the discharged caps will pull a high current spike when they recharge and can cause sparking, people have destroyed the connectors this way and in at least one case, the MCU fried (Rehab1's ACM). Either use a XT-90 with "spark arrestor" or use small resistors (if you don't know what I mean or how, then don't try it, I don't have the time to draw a diagram right now ) between the battery and mainboard connectors first to recharge the caps, then connect normally.
  4. The ubiquitous term used most commonly has been "wheel" ("wheels" for plural) for years now.
  5. I don't actually check the voltages themselves, but over the last winters, I've stored the wheels discharged to something like 30-40% for 6-7 months at a time, and they've never discharged enough to even drop much, ie. looking at the LEDs showing the charge, I've had 3-4 LEDs on out of 9 on both KS16's when putting them to storage and still had 3 LEDs on in the spring. All batteries were left connected to the wheels, since KS's don't draw power from them when off (most wheels don't, with the exception of Ninebot Z-series which have relatively huge vampire drain that sucks full batteries to empty in about a month or so, those things need to be charged often during storage, or preferably, disconnected from the wheel mainboard!). For other than Ninebot Z's, likely the only thing using power when the wheel is off is the BMS, and the current it draws seems to be somewhere in the microampere-range, and then it won't matter if the packs are connected to the wheel or not. Four 16S1P -packs each with their own BMSs I've stored in a ground basement under the house, that has temperatures ranging from freezing to maybe 15-20C, have been there for about 2-3 years without charging in-between, when I checked this spring, they were around 56V (I think I charged them to around 57-57.5V when I put them there).
  6. The ACS712 is a current sensor microchip using the hall-effect (magnetic field caused by flowing current) to measure the amount of current and output it as an analog voltage signal. https://www.allegromicro.com/~/media/Files/Datasheets/ACS712-Datasheet.ashx My best guess would be that the controller might go into some sort of overvoltage lockout if the motor isn't turning and it senses too high voltage (48V controller sounds like it's meant for something like 11S or 13S batteries). Have you tried discharging the batteries to a lower voltage to see if it then starts running? Then again, if it starts running without load (if you mean you turned the bike upside down by "backwards"), it might be related to the ACS712 (controller detects overcurrent when the motor's still stalled at start-up), in which case maybe a small voltage divider to drop the detected current value might work? EDIT: No, it won't work, the sensor's bidirectional, so it would move the offset away from the "zero current" -point at half the supply voltage, it would need a more complex set up with an op-amp or such... But I'm really just guessing... Either way, perhaps it would be best to get a controller that has suitable maximum voltage for the batteries? A better place to ask might be something like the Endless Sphere (e-bike) forums: https://endless-sphere.com/forums/
  7. Yeah, time has flown pretty fast looking back. I removed the foam after the first summer, no video though Not that there'd be much to see, I purposefully used a crappy 2-sided tape (not the 3M-stuff) that was easy to peel off and left without leaving marks. If it would have left residue, I'd have just cleaned it off with IPA anyway... But here it is in its original beauty: <3
  8. Yeah, the funny thing is that the price has stayed pretty much the same since the release. Guess there's enough demand for them still that there's no need to drop the price. I've been happy with mine, zero issues after 3 summers and while I haven't measured the actual battery capacity since the first summer, I haven't noticed a drop in the capacity so far (although likely after that long there is some).
  9. I guess they're pretty random. But you could try mailing them directly and ask. The owner seems like a nice guy.
  10. Yeah, the sale price is only for the 420Wh version. Check out other possible options here:
  11. 1RadWerkstatt: https://www.1radwerkstatt.de/epages/80603321.sf/en_GB/?ObjectPath=/Shops/80603321/Products/KS16[1] Currently 1029€ for the 420Wh version, 1449€ for 840Wh. Free shipping within EU-area. Bought my KS16S (White, 840Wh) from there in the spring of 2017.
  12. Pari kertaa varmaan sen ajolasi-tyypin nähnyt, yliopiston liepeillä ja uudelleen Tourulan suuntaan menossa, musta pyörä leveällä renkaalla, näytti Ninebot Z:lta. Omat ajelut loppui tältä vuodelta tällä viikolla kun tiet oli jäässä aamuisin jo heti alkuviikosta, ja näyttäisi että lämpö pysyttelee nollan alapuolella tästä eteenpäin.
  13. @EUC Extreme käytti ruuvattavia nastoja, ilmeisesti pito on erittäinkin riittävä "normaalissa" ajossa, tosin nastat taisi olla verrattain kalliita (luokkaa ~100€ / rengas?). EDIT: Muistelisin että ulkokumeissa on käytetty jotain vahvikkeita (kevlaria?) sisäpuolelle liimattuna ettei nastat puhkaise sisäkumia, joten jonkun verran värkkäämistä noissa on.
  14. RECOM also does board-mountable switching-modules with isolation and whatnot, but the issue is the price. If the end user should be able to build / buy the parts for about 25-30€ total or less, the module alone would pretty much eat the entire budget
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