ElectricWheelEric Posted October 1, 2016 Share Posted October 1, 2016 Piggybacking is frankly a pathetic way of testing. dyno-rig is good idea,and all the others whoi commented it with some concerns they are all right about them. the fact is that GotWay @Linnea Lin Gotway @Jane Mo and all the rest of the gotway stuff wants only $$$'s money,they increase their profit by reducing cost buying crap materials. ignorant about health & safety,dont care at all, and when someone injuries him/herself then all they could say is that they were riding it inappropriatley..what a bunch of 1d1ots and loads of cr@p. there should be an EUC factory in the Us and in the UK and leave GotWay and their sh1t to disappear from market, fed up with their cr@p for sure.I wish they go bankcrupt one day,then i will open a champagne! Link to comment Share on other sites More sharing options...
Donafello Posted October 1, 2016 Author Share Posted October 1, 2016 4 hours ago, ElectricWheelEric said: Piggybacking is frankly a pathetic way of testing. dyno-rig is good idea,and all the others whoi commented it with some concerns they are all right about them. the fact is that GotWay @Linnea Lin Gotway @Jane Mo and all the rest of the gotway stuff wants only $$$'s money,they increase their profit by reducing cost buying crap materials. ignorant about health & safety,dont care at all, and when someone injuries him/herself then all they could say is that they were riding it inappropriatley..what a bunch of 1d1ots and loads of cr@p. there should be an EUC factory in the Us and in the UK and leave GotWay and their sh1t to disappear from market, fed up with their cr@p for sure.I wish they go bankcrupt one day,then i will open a champagne! I have to agree with you on the piggybacking but I can pretty much bet that there is a lot more testing thats done then they make it out to be. we get a lot of small bots of info from gotway and usually wont get a answer when we question there responce which is the only compliant I have with them. I have owned the Msuper V2 680wh for 3 months and then sold it and bought a 850wh V2 and its lasted a year and I have not had one incident with either unit. And trust me my first wheel took a beating and still ran flawlessly. Now you stated that they are using cheaper parts and crap materials. Do you own one of the V3's or the new ACM? My only gripe with gotway is the lack of info and support we get from them when we have questions or when products are releasing. Its been over a month since the annouced the new 16xx models and still unit this day they have not gave us any real info except little bits here and there. when I laid out this $2,000 I told myself that there is a chance that i'm just throwing this money down the tubes and yet I still made the purchase because they are the best as far as high end units go Link to comment Share on other sites More sharing options...
pArmitage Posted October 3, 2016 Share Posted October 3, 2016 On 10/1/2016 at 4:52 AM, ElectricWheelEric said: Piggybacking is frankly a pathetic way of testing. dyno-rig is good idea,and all the others whoi commented it with some concerns they are all right about them. the fact is that GotWay @Linnea Lin Gotway @Jane Mo and all the rest of the gotway stuff wants only $$$'s money,they increase their profit by reducing cost buying crap materials. ignorant about health & safety,dont care at all, and when someone injuries him/herself then all they could say is that they were riding it inappropriatley..what a bunch of 1d1ots and loads of cr@p. there should be an EUC factory in the Us and in the UK and leave GotWay and their sh1t to disappear from market, fed up with their cr@p for sure.I wish they go bankcrupt one day,then i will open a champagne! Neither name calling nor wishing ill of the company is going to help the situation. If you don't have something constructive to say, it's best to keep it to yourself. The V2 dumped riders when they pushed the batteries too hard. Now, as I understand, the V3 has a tiltback function. My guess is because we, as the community, pointed out to Gotway that this is what we wanted. And it got done without insulting anyone's intelligence or moral compass. Further, they specifically market the V3 as going slower than it really CAN go, in order to help keep people from trying to go too fast and hurting themselves. So much for being "ignorant about health & safety,dont care at all," [sic]. Much like what happened here in the States with Jack-in-the-Box, where 12 people, including 3 children, (IIRC) got incredibly sick and died from food poisoning. Today, there is a Jack-in-the-Box around the corner from my house. They KILLED people, yet they're still around. Why? Because the company made changes. They improved. Accidents happen, and at times it's tragic, but it's not as if the spawn of Satan runs the company. The same can and should be said of Gotway and their products, and the worst I've heard from this forum has been busted knuckles and a concussion, both of which, while unfortunate, could have been prevented with safety gear. As long as Gotway maintains committed to delivering quality products and improving them both in terms of performance AND safety (not necessarily in that order), which they have demonstrated simply by having a presence not only on these forums but in this very topic itself, they should have a dedicated userbase committed to giving them feedback when they fail, and giving them praise when they shine. This does not mean that they're off the hook, of course. I personally was ready to make a purchase last month until this issue came to light. And until I hear better, they're not getting my money. Hitting a company in the wallet is far more effective than belittling their sales representatives. Link to comment Share on other sites More sharing options...
Keith Posted October 3, 2016 Share Posted October 3, 2016 On 1 October 2016 at 11:52 AM, ElectricWheelEric said: there should be an EUC factory in the US and in the UK There is: Solowheel in the US and Uniwheel in the UK - both are, of course, struggling to cope under the massive weight of orders. ??? Link to comment Share on other sites More sharing options...
Jason McNeil Posted October 3, 2016 Share Posted October 3, 2016 1 hour ago, Keith said: There is Solowheel Actually, these are also assembled in Shenzhen, as far as I'm aware, all components are sourced in China. Link to comment Share on other sites More sharing options...
Keith Posted October 3, 2016 Share Posted October 3, 2016 37 minutes ago, Jason McNeil said: Actually, these are also assembled in Shenzhen, as far as I'm aware, all components are sourced in China. Jason, given this post: it looks like the Uniwheel, or st least it's parts, may well be as well. Always assuming it ever actually gets manufactured. I guess they must still be doing extensive quality and safety testing! ? Link to comment Share on other sites More sharing options...
Rehab1 Posted October 3, 2016 Share Posted October 3, 2016 On 9/29/2016 at 5:46 AM, Greg Spalding said: I'm realizing on my own that this image I created looks somewhat crude. This was not what I intended when so made it. I apologize if I offended anyone. Here is another one. Damn...I missed something here! What was crude about your avatar image? Did your image pass @HunkaHunkaBurningLove's standards for being crude? If so.. probably best you pulled the sucker! Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted April 25, 2017 Share Posted April 25, 2017 On 9/26/2016 at 2:53 PM, esaj said: Sorry, the quote was taken a bit out of context (regarding burning mainboards)... the 140A number is got as follows: -Put 16 cells with 30 milliohms each in series, coming to a total resistance of 480 milliohms = 0.48 ohms (assuming zero resistance between the cell connections) -Assume a short-circuit with totally zero resistance (which of course is not reality) between the terminals of first and last cell -Assume that the cells are loaded to full voltage, 4.2V per cell = 67.2V total Voltage drop over the entire circuit is 67.2V over a resistance of 0.48ohms: I = U/R = 67.2V / 0.48ohm = 140A Of course this is a totally theoretical figure (the total resistance of the circuit in reality will always be more than the internal resistances of the cells). And why would you short circuit the pack anyway? But, should that happen for whatever reason, the momentary current spike can reach very high values, easily enough to fry something in the circuit (most likely the mosfets on the mainboard in case of a half-bridge shoot-through). Of course the cells should never be used under such conditions for any length of time, even if they won't downright catch fire or explode, they'll still probably suffer at least some damage... Yep, the internal resistance will drop the voltage, but the current passing through a series circuit is the same for each component, and with multiple packs in parallel, the absolute maximum amperage of the components is likely exceeded by a very large factor. That's why we have BMSs to cut the power under short circuits or such (but even they may not react fast enough to save the components). Ha, I still don't consider myself an "expert" when it comes to electronics... More like "happy-go-lucky"-amateur. I though the MOSFETs on the board are rated for continuous amps around that level. and I though also the momentary surge was a couple of hundred amps. also not to forget the pulse is going into a motor coil adding more resistance and inductance. So I would think nothing near 140 amps. IRFB3207ZGPbF(Package Limited) 120A. Pulsed 670A. So if my datasheet is correct, what is blowing the MOSFET? I have seen some designs that put a zener diode on the Gate to prevent voltage spikes damaging the Gate. Link to comment Share on other sites More sharing options...
esaj Posted April 25, 2017 Share Posted April 25, 2017 15 minutes ago, Carlos E Rodriguez said: I though the MOSFETs on the board are rated for continuous amps around that level. and I though also the momentary surge was a couple of hundred amps. also not to forget the pulse is going into a motor coil adding more resistance and inductance. So I would think nothing near 140 amps. It was a simplified example of a single battery pack being short-circuited through an "ideal" 0-resistance wire. Quote IRFB3207ZGPbF(Package Limited) 120A. Pulsed 670A. So if my datasheet is correct, what is blowing the MOSFET? I have seen some designs that put a zener diode on the Gate to prevent voltage spikes damaging the Gate. The numbers in the datasheet are purely theoretical, usually assuming an "infinite heatsink" and such. They do have their uses in the sense that since (more or less) every manufacturer uses the same way of reporting those values, you can compare the values between mosfets, but you should never assume you can go that high in real life circumstances. This quote from Olin Lathrop in electronics.stackexchange.com sums it up pretty good: Yup, that's the way MOSFET datasheets work. The maximum current rating really means "This is the maximum current you can ever possibly get thru this thing, if you were to somehow not violate other specs in the process, although we have no idea how to do that. We put this here because we think it's cool, and maybe someone is dumb enough to buy a truckload of them before realizing they can't actually run the part at this value for any set of real world conditions." Basically, each of the limits of the device are specified separately. You have to look at what you're doing and carefully check each one. The real limit on current is usually die temperature. To check that, look at the max Rdson for your gate drive level, compute the dissipation due to your current, multiply that by the die to ambient thermal resistance, add that to your ambient temperature, and compare the result to the maximum die operating temperature. When you figure all this backwards to find the maximum current the device can take before overheating, you'll usually find that's well below the absolute maximum current spec. (from http://electronics.stackexchange.com/a/216944/128374 ) If you dig the mosfet datasheets deeper, you will find a graph showing the "safe operating area" (SOA) under different conditions, but even there the case (package) is usually assumed to be at 25 degrees C, and should be derated further according to how hot it is expected to go (as well as taking a lot of other limitations and characteristics into account, that's why there are so many numbers and graphs in the sheets). This is from IRFP4368, used in new KS16S's. Note that it says Tc = 25 (case temperature) and Tj = 175 (junction temperature). Link to comment Share on other sites More sharing options...
aMADs Posted May 6, 2017 Share Posted May 6, 2017 В начале темы моего видео, и поэтому, при покупке в течение 2 -х недель, сгоревшего 2 материнской платы, то у нас была зима, снег, я не брал много, в этом году лето и на материнской плате снова сгорел. Уже третий в одном колесе. Продавец просит отправить его, но плата за ИБП составляет 112 €. Я думаю , что это слишком дорого для простого участка. Я пригласил продавец отправить по обычной почте. Но нет ответа еще не .а мой +1640 Link to comment Share on other sites More sharing options...
MaxLinux Posted May 6, 2017 Share Posted May 6, 2017 On 10/3/2016 at 0:49 PM, Keith said: There is: Solowheel in the US and Uniwheel in the UK - both are, of course, struggling to cope under the massive weight of orders. ??? How to improve number of orders: 1. Solowheel: end ridiculous overpricing 2. Uniwheel: have a wheel that actually exists that people can actually buy Link to comment Share on other sites More sharing options...
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