Techos78

I regularly use EUC-Watch, almost perfect for me, I really appreciate knowing my speed...etc. But I think it is necessary to improve the TOP SPEED data, which is destroyed as soon as there is a BT link fault. It therefore seems to me necessary to filter and reject any inconsistent value (no, I do not drive at 250 km/h). It is tolerable to have a glitch or a freeze on the speed measurement, but the TOP data is memorized, it must be made reliable. Probably by carrying out the difference between two consecutive speeds (the acceleration) and by rejecting the absurd values. It is better to inhibit a "good" value than to memorize a "wacky" value. IMO as Elon says... @enaon : Is bangle.js 2 a really credible solution, compared to Rock watch? Does it have or will have a serious application manual to avoid having to play guessing games?

I'm testing this graph, and you're right to like it: it's nice and useful, I appreciate it too. But I have a difficulty : the time axis is reversed: the past is on the right and the present on the left. It seems to me that it would be better to have the present on the right and scroll the samples to the left Just a notice, i can reverse my old brain .

No, not the good chipset...

The best use of the button is the horn, active when the speed is above 2 km/h. Currently it doesn't work on v11, but I guess @enaon will be able to implement this function when he will have a wheel "on the shelf". I really like this watch, I can't drive without it ...

Yes, you're right, here is a comparison with a gps speed (IM-V11) : I'm going to rectify that ... I didn't expect to drive that fast, it's important to be aware of that. About negative speed in backwards driving, it's a bad idea because there is not enough width with a large font : and the color change thresholds do not work. (between 12 and 14 mph)

@BarrettJ : We do not have the same configuration :

OK for colours, i understood. Just a comment: I think the red is too dark, it is difficult to see despite the absence of sun at this time. In Mph ? Mmmmh, it is possible, I will take a look, Thanks.

My v11 firmware: and some data

I just looked at the official Inmotion app: the reverse speed is positive. For me, that don't care... I installed ALL modules from P8 loader via Windows/Chrome PC. Speed works fine, but ... nothing else . but it's a good start. While driving I have many vibrations of the watch, when I display the speed in large characters the speed changes to reverse colour at 13 km/h ... I have tried programming the haptics thresholds, without results, however I am very happy with the current state, I have been waiting for this for years. @enaon is very efficient, he will certainly be able to improve all that, calmly, taking the necessary time...

When moving backwards, the speed of V11 is negative. This is not the case for Kingsong because my old wheels are reversible.

No, not always in the KS packs because bms are not always equipped with components that balance the cells. The first pack (2 packs cascaded in 16b, 2 packs in // in 16s) of my own ks16b-840Wh died also after 16 months, the voltages of 16S2P chain were: 4.17 , 4.17 , 4.17 , 4.12 , 4.16 , 4.14 , 4.15 , 4.17 , 4.17 , 4.12 , 0.00 , 4.17 , 4.17 , 4.17 , 4.17 , 4.17 total: 62.3 Volts Inside blue, 2 mosfets in // to stop the charge inside red, 2 schottky diodes in // to prevent voltage back to the port inside yellow, nothing nothing nothing, ks saved 2 € by eliminating balancing ! ! ! The different thresholds managed by the bms are about that: In packs that have no balancing, the first pair of cells that reaches the threshold "Overcharge protection" stops charging by blocking input mosfets. Not so glorious but it works pretty much. There are two evil effects: -- there is no ultimate protection, in case of failure the pack burns, the wheel burns, the room and the building burn and so on -- more seriously, the pair of cells of smaller capacity reaches the stop threshold first, but it discharges faster .. etc. The voltage variation is greater and thus aging accelerates compared to others. The effect is cumulative, and the weakest pair dies, naturally after the guarantee ... This is why the rules of the art of Li-Ion management theoretically impose a balancing, but traders prefer programmed obsolescence ... I saw that the ks18s is equipped with balancing, for others I do not know.

I suppose this frame can receive a damper to suspend the wheel...

Remember: when they want it, the Chinese are doing technological marvels. There is currently a rover exploring the moon, they have their own space station that they feed semi-automatically ... we do not know how to do that, not just for lack of money, but because it's very difficult (I worked on Ariane 5).

This opinion is a little severe. I do not think the Chinese are producing low-end products voluntarily. They create cheap items in many copies, it's their niche. All this is done by very young people, who are terribly inexperienced. Pedal problems of KS, connection problems of GW ... are almost unimaginable in the West ... I hope.

This pack 420 Wh (16s2p, 3500mAh) is from my ks16b-840 bought in Paris in April 2016 at Gyroroue-Shop. This wheel is part of the first batch available in France and transported by plane, the other versions (680Wh and below) were transported by boat. At the beginning of 2016, we had seen a ks16a prototype, but it was the ks16b that was delivered. I really like kingsong wheels, but of course the first versions can not be perfect, and we are beta testers. It took 100 years to improve the reliability of automobiles, I hope it will be faster for electric wheels... Other thing, you can notice that there is no limitation of output current, using several large mosfets in parallel. This is fine, only the motherboard has to manage the current (also with a 40 A fuse), it is important for the safety of the driver. If you use a generic pack, you must inhibit the current limitation of the bms by a strap.

Unfortunately, this requires opening the pack. Then cell-by-cell measurements are very easy : As you can see, there is no component for the balancing function ( yellow rectangles ) There are two excellent schottky diodes in // to protect the charge port ( red rectangle) And two mosfets in // to interrupt the charge when the first cell reaches 4.2 Volts (blue rectangle).

Thanks to Keith for his explanations (page 2), I'm an electronics engineer and I approve what he said ... except the two sentences above. I have my dead pack under the eyes, yes two cells in // are shorted, no they do not sweat. I'm not sure that the pack can give much power (this is not necessary in a cascade configuration), but I measure 0.00 V, short-circuited cells have a very low impedance. Maybe I'm out of luck, but we can not say that the phenomenon is very rare ... 300 € in the trash, rhaaaa.

you need an application that can display negative currents. I saw a WheelLog that was recompiled, and there was no problem. It's just an hypothesis ... a bit off topic, sorry. Very good news. I was worried because I had almost the same problem after 18 months on my ks16b (April 2016), impossible to charge beyond 63 V. I measured all the cells and I saw 15 times ~ 4,2 V and a cell (in fact a pair) at 0 V (ie in short circuit). In the ks16b, both packs are cascading (i.e. not in parallel), this is the first pack after the charge port that is dead. In this old battery pack, there was no balancing component, and I really really hope that KS has now corrected this severe mistake.

I think it's not a bug. Now, KS wheels use signed current values. Old versions of WheelLog give huge values when the current is negative because msb is 1. Then, when the current is >600, you have to subtract 655.35 Amperes to have good value. The power is simply the product voltage * current. You have to upgrade WheelLog, last version is OK.