meepmeepmayer

Cool, EUCs now have mystery fluids

Not sure what is going on here, but this is the video thread. Fights go in their own place please

Sorry for you! Any chance you can fix this somehow and ride again?

Here I made a schematic how things should be (I think - I'm going by my ACM and assume the MCM5 is the same). It's an MCM5 800Wh right? Two battery packs, one big, one small? - 1 are two tiny connectors, from thinner cables only connecting the two battery packs directly (they are wires for fine balancing, I think, and also the charge cables.). Disconnect those two tiny connectors first, and then keep them apart. 2 and 3 are the big yellow plugs for the main power cables of the battery packs. You disconnect one of them, see if the other pack charges, and vice versa. Just don't have both plugged in at the same time if a battery pack has been charged to 100%. Only one pack at a time may be plugged in then. That's all The mess in the MCM5 may make it look more complicated than it is. The Y cable may not immediately look like one, in my wheel one end is much longer than the other and goes to the other side, but you only need to find the two battery ends of this cable. If your wheel looks somehow different than this picture, then we have to look what is different. But I think this is how the relevant connections are made. And just remember what you are trying to do: you disconnect all but one battery pack, test if the one connected pack is good by seeing if you can charge it to 100%, and you do that for every pack (two here, but would work for however many packs you have). While you do test the packs individually this way, you just need to be careful never to have two packs with different voltages (= charge states) electrically connected. edit: I'm a bit confused where the charging cabling comes in play. This schematic might not be completely right. I think I confused myself I'll figure this out some other time.

I forgot, between the batteries there should also be thinner cables with two tiny plugs. These also need to be disconnected, of course, before you charge one battery but not the other. So disconnect those two tiny plugs before you do anything else, and never connect them again, they are not needed now. (I edited that into the bigger post above as the new first step.)

You only plug in or unplug one of two yellow connectors (going to one or the other battery pack). It's not more complicated than that. Only thing you should not do is re-connect both packs if they have different voltages (= charge states). That is what I meant to convey. Though you could ride with only the one working battery connected until that battery is back at 85%, and then you can again connect the other, damaged battery. They will have the same voltage so plugging them together is ok, and charging will be limited to 85% again because it's limited by the weakest pack, but then you would be back to where you are now. But riding with a damaged pack can be dangerous, so you already lost one of the two packs. Yes exactly.

There should be a Y-connector somewhere where the two cables from the two packs come together. From there it's one cable to the board. That connector is where you work. edit There should be some thinner cables between the battery packs, with two tiny plugs. Disconnect those and then forget about them (never re-connect). I forgot those earlier. Disconnect one pack (A), keep the other (B) connected (speaking of the main power cables with the big yellow plugs). See how far the connected pack (B) charges. Disconnect it (B)! No packs are connected to anything now. Connect only the other pack (A) and see how far that one charges. Now you know which pack is damaged: the one that doesn't charge to 100%. If one pack charges and the other doesn't, you can't connect them together again!! Sounds more complicated than it is. You merely individually connect pack after pack (each alone) and see if it charges, and you never connect differently charged packs. If you electrically connect different voltage packs in any way, power will rapidly (and uncontrolledly) flow from the higher voltage one to the lower voltage one as they try to balance out. Possibly give a spark, melt some cables, produce a short that fries the entire wheel, or make the lower voltage pack go up in flames (worst case). So charging both packs individually assumes one of them is damaged and will never be used/connected to the other again. And if you ever need to connect two working packs with different voltages, charge them individually in the wheel, to the same voltage (just charge them to 100%), before making any connection between them. I hope for you that the big pack is ok and only the small one damaged. Chances are 1 to 2 so *knock on wood* (For the same reason, be very careful not to accidentally short a pack when using the electric tester by having the test probes touch when they shouldn't.) (For the same reason, when you connect any pack (some voltage) to the board (no voltage), do it quickly so there is no chance for a spark. This is not a big concern, but helpful to know.) TLDR: Do not make any electrical connection between battery packs with different voltages. They must be roughly the same voltage before they may connect. No need to be scared, just to be aware how electricity behaves on a basic level (I'm certainly no expert!)

Ok, so I don't know how this works, and I'm guessing here, but: 84%-85% (which app?) corresponds to ~79.75V (assuming the normal algorithm where 3.3V per cell = 0% and 4.1125V and above per cell counts as 100%). 19 * 4.2V = 79.8V which is the same number. So it looks like you may have one bad cell in series somewhere, so you get 19*4.2V = 97.8V = 85% instead of 20*4.2V = 84V = 100% = as it should be. (If this is how this works, I'm not sure.) So: bad pack with a bad cell somewhere. Can you charge the wheel with only one of the packs connected, for each pack, and see if you get to 100%? Then you know which pack is bad (I think the MCM5 has two packs) (Be careful re-connecting packs with different voltages!!) edit: I just saw that @mrelwood already made the same argument. I don't think it's likely to be anything but a bad cell causing your troubles.

That's normal and very healthy

Wow! I expected it to be a V10F successor, but now the bigger number (12) makes more sense. Looks like IM is ramping up their efforts!

The bottleneck (weakest link) is always going to be somewhere. If we assume super thick motor power cables (which we semi-have because of the heat sleeves on the too thin wires), I think it will be either the mosfets or the battery (less the power delivery limit from the battery, but more that you don't want to waste crazy amount of your battery just to get stronger acceleration, so the firmware has to say "Stop!" somewhere). Which is good. The mosfets have the temperature sensor that (in theory) should warn you before they die. And if the battery gets to its limits, you merely faceplant, but the wheel doesn't die. - We've also seen some capacitor failures (might just have been from shorts) on the super high power wheels, so beefing those up can't hurt. In the end, there aren't too many components. Motors should be crazy strong in comparison to all other components. In the end, unless something in the motor melts or it gets so hot it demagnetizes the magnets, what can fail? The motor is simply much bigger than any other component so it won't die first. - That's the (my) "I guess so" first approximation theory. Who knows how reality is...

They are getting (way too) hot. That's why they have individual fiberglass heat sleeves - to prevent them from melting together and shorting. That's not how you are supposed to build electronics. Cables are supposed to be cool. If they get hot or even warm, they're too thin. With the limited axle space gone, there's no excuse for that now.

That motor looks NICE! Clean windings! Robust. Wow! All that is missing is... ... that. Well, maybe next time Can't wait to see an EX motor disassembed!

What is the final weight?

That Vee video is hilarious in how she describes the "Gotway characteristics" of the wheel Also, she calls it "Ex", like X. Is it EX (Eee-Ex) or Ex (Ecks)? I still wonder if it veers left slightly due to the asymmetric battery distribution (like the Monster).

No But 1800Wh is 100V and 4p (with 21700s) and these wheels have that battery configuration. Nobody would argue that an MSP e.g. is too easy to overlean. So it looks like 4p is where the KujizoneTM starts. Of course more is always better, but what else is new Yep, making it 8p. But there's the 1800Wh 100V too.

4p seems to be fine, especially with the new 21700 cells. MSP, RS, Nikola 1800Wh are all that. Wasn't a problem with the Tesla (for example, 4p 18650) either. Of course the bigger battery beasts (Sherman!) are even better. So I say 3p seems not enough, and KS firmware might rather limit too early maybe, who knows. Anyways, this is a first world problem. Ride "normally" and the S18 is a very fine wheel (if you can't tell, I wouldn't mind one, looks nice and is comfortable).

Please ignore all motor power ratings! They mean mostly nothing and aren't precise. The S18 "problem" is the battery. It's 3p (three blocks of cells in parallel) which limits the max power output. So in that sense your Z10 (4p) is stronger - but it's different types of battery cells so not necessarily comparable. That alone is still no problem unless you go too fast or accelerate too hard at speed. But such a small battery isn't enough for really high performance riding (fast plus hard accelerations at speed). So just ride non-extremely, the 45kph speed warning is a good idea, and don't do Kuji-style crazy accelerations. Then you should be good. Look at what Chooch (Youtube) does on the S18, it is certainly no weak wheel! And very fun and comfortable apparently. And looks nice

You overleaned the wheel, and the crash damaged a part which made you crash again. So far, no reason to distrust the wheel. Crashes that are pure unexpected hardware failures with no prior history are extremely rare, unlike the typical overlean crashes. So the only question is: is the S18 good for going 50kph? Personally, for a fast wheel like this, I would add a 10kph error margin just to be sure. So if you want to go 50kph, the wheel must be able to go 60kph without any problems or even just alarms or tiltback. So the S18 would be a mostly-40kph wheel for me. Others might disagree with that. That's the key question here. Were you simply too fast, or were you riding reasonably but the wheel wasn't strong enough for it?

Someone get Phantomas to melt his motor wiring!! Maybe we'll be getting proper cable gauges then

Not sure if putting in ready-made run-of-the-mill speakers that only need connection to a power source needs a lot of engineering resources. But you are right in the sense that the presence of speakers (and colorful LEDs) can distract buyers from noticing the absence of the more important aspects you mentioned (waterproofing etc.). So I agree in the sense that speakers might needlessly consume resources: the wheel buyers' attention. And some people seem to like having speakers in their wheel. They can be useful (custom wheel sounds for example). Anyways, as long as the speakers don't hide deeper shortcomings, I don't have anything against them. Complaining about some tiny PEV's speakers while noisy cars and motorbikes are considered normal doesn't get my approval.

"Teton Gravity Research" I guess they fall a lot. I'll have a look.

People who have both an 18XL and 16X tend to prefer the 16X, I believe. (I have neither.)

This is what the forum is there for. And there are no stupid questions if they are asked in good faith. Also, it's completely normal to be worried about every slightest unexplained sound your first wheel makes. Everyone does that Enjoy the Tesla!