Cloud Posted September 12, 2015 Share Posted September 12, 2015 My kingsong tilts back upon overheating quite often, sometimes after riding for 10- 20 minutes. Is this a good safety feature or a design flaw - inability to shed heat effectively ? Or..i am I just too freaking fat? ( i am 100kg) which causes the wheel to overheat much faster. The wheel is supposed to be rated for 120kg though.i dont have data on how other wheels react to overheating.Opinions welcome. Link to comment Share on other sites More sharing options...
Jason McNeil Posted September 12, 2015 Share Posted September 12, 2015 Many hills involved? It could be voltage sag phenomenon: http://forum.electricunicycle.org/topic/1055-usable-wh-in-ks-680wh-only-~500wh Link to comment Share on other sites More sharing options...
Cloud Posted September 12, 2015 Author Share Posted September 12, 2015 @Jason McNeilI dont believe this is voltage sag. Sometimes when this happens no hills are involved. Sometimes ive been riding fast, sometimes slow. It happens equally often on full battery as it does on empty. It happens more when its hotter outside ( afternoon) than when its cooler ( evening). It tilts back and forth and beeps. It will continue doing that until you shut it off. If you turn it back on immediately after or too soon, it will start tilting and beeping again. You have to wait a minute, sometimes 2 minutes. If you wait a bit and turn it on, it may work normally for a minute or two , or five and then it happens again. If you wait longer while its off, then you can ride longer before it happens again. All of this is telling me this is related to overheating Link to comment Share on other sites More sharing options...
Jason McNeil Posted September 12, 2015 Share Posted September 12, 2015 What temperature is the King Song App reporting & voltage when this happens to you? Link to comment Share on other sites More sharing options...
Cloud Posted September 12, 2015 Author Share Posted September 12, 2015 I still havent connected to the app. I dont have an android phone( Link to comment Share on other sites More sharing options...
Jason McNeil Posted September 12, 2015 Share Posted September 12, 2015 Please borrow one, it will give more insight into the problem, whether it's either temperature voltage related. Gimlet has a KS 800 & has seen this only during extended climbs up hills. Link to comment Share on other sites More sharing options...
Cloud Posted September 12, 2015 Author Share Posted September 12, 2015 I will try to get the android phone. Ive had tiltback happen when climbing a hill especially on a lower battery but that was a different kind of tiltback and beeping pattern. What happens here is that it tilts back and forth, back and forth, back and forth..even after youve stopped and gotten off the unit, and produces a single beep about once per second, beeping continues until you shut it off. I will try to get a temperature reading Link to comment Share on other sites More sharing options...
KaleOsaurusRex Posted September 12, 2015 Share Posted September 12, 2015 The King Song warranty from the manufacturer covers the important parts: main board, batteries, and motor. Service would be offered through the distributor.Following this closely; looking forward to resolution of the issue. Link to comment Share on other sites More sharing options...
Gimlet Posted September 12, 2015 Share Posted September 12, 2015 I've come to the conclusion that it's not really an issue. It is probably the voltage drop the same as mine and it's basically that the KS is too powerful for present battery technology but it's much better to have that power to keep you safe than it is to reduce the power to something the batteries can keep up with. It handles the situation very safely by tilting and forcing you to dismount until the battery has recovered.Jason tells me the new board has reduced the voltage threshold from 54v down to 50v and this is sure to delay the behaviour a little but if you are heavey, going up steep hills at relatively high speeds it's still going g to happen eventually. Obviously because it's a high power draw situation it will always conside with the motor being fairly hot to touch but I'm fairly sure that's not the problem. Link to comment Share on other sites More sharing options...
Cloud Posted September 12, 2015 Author Share Posted September 12, 2015 The King Song warranty from the manufacturer covers the important parts: main board, batteries, and motor. Service would be offered through the distributor.Following this closely; looking forward to resolution of the issue.At this point i dont think there is anything wrong with this particular wheel. Its is either too safe and wants to protect from overheating by a big margin or not that efficient in heat dissipation. I hope to get an android phone today or tomorrow to find out the temperature Link to comment Share on other sites More sharing options...
KaleOsaurusRex Posted September 12, 2015 Share Posted September 12, 2015 I'm going to follow up with King Song personally, and I'm sure Jason will too. If we can help get this resolved in future designs, and maybe make it possible to modify the unit you have already, we will. I guess figuring this type of issue out is just part of being an early adopter.It sounds like the adjustment in voltage threshold that Jason already pushed for, implemented in this newest wave of units, may address the issue. Perhaps a simple main board replacement would make your unit more ridable if it's a major inconvenience?There could be a combination of small solutions that would solve the problem, like the adjusted voltage threshold plus an extra heatsink, plus different battery. I know Jason is already encouraging King Song to consider a slightly different battery design. The goal would be to retain this safety behavior but make the necessary changes to postpone it as long as possible.If nothing else, we distributors should figure out a more realistic estimate of how heavy the rider must be before this becomes an issue. Link to comment Share on other sites More sharing options...
Gimlet Posted September 12, 2015 Share Posted September 12, 2015 With me it's a combination of my 90+Kg and the long steep hills I like to go up at speed.The better batteries that can run continuously at a higher output would obviously be the answer but the batteries used presently are one of the high price parts of the wheel and if you upgrade to the latest batteries there will obviously be a significant price implication. Latest best technology always comes at a high price! Link to comment Share on other sites More sharing options...
SirGeraint Posted September 12, 2015 Share Posted September 12, 2015 At this point i dont think there is anything wrong with this particular wheel. Its is either too safe and wants to protect from overheating by a big margin or not that efficient in heat dissipation. I hope to get an android phone today or tomorrow to find out the temperatureMy 9B1 tilts-back at around 140 degrees Fahrenheit (around 60 degrees Celsius). I reach 138 and 139 on many days. I am heavy, it's usually been 93 - 96 degrees F outside. Only moderate hills. So in the heat of the summer (like 100 F) I might not be able to ride my trails without a cooling off break.I hope the King Songs aren't tilting-back sooner since right now I am thinking a KS16 or Gotway 16 will be my next EU. Link to comment Share on other sites More sharing options...
Gimlet Posted September 12, 2015 Share Posted September 12, 2015 If its the battery voltage limitation which we know behaves like that in the KS then it will affect all high power wheels, more so on smaller batteries as the voltage drop occurs more quickly.This being the case the only solution is better batteries but that will be expensive at present. Battery technology is improving at a hell of a pace and within a year or three it's likely the batteries will be cheaper and more capable. Link to comment Share on other sites More sharing options...
Gaston Posted September 12, 2015 Share Posted September 12, 2015 I know a similar case from a faulty cell in a battery pack of a Firewheel. This one still runs at around 40 V with no problems. A control board must support undervoltage lower than 50V to cope with such failures, but should give a note to the driver.Maybe the KS tries in undervoltage condition to keep the estimated W value with rising current and so overheats the MOFETs. Is the KS temperature derived from the control board or a sensor inside the motor? As the KS has some roots of the Gotway I would think it's derived from the control board. Link to comment Share on other sites More sharing options...
Gimlet Posted September 13, 2015 Share Posted September 13, 2015 Even Tesla progressively restrict the available power in their cars when you've been driving it hard for a while.Apparently it can only get about two thirds of the way around the Nurbergring before the limitations kick in. They don't turn the power back though until you are reaching the batteries output limit.King Song is doing a similar thing in my opinion except that it wouldn't be safe to turn the available power down so they just force you to stop for a moment to let the batteries recover. It's nothing to do with the state of charge of the batteries as I've had it happen after just 5km on a full battery, it's purely to do with the internal resistance and how quickly it can deliver it's stored power. Link to comment Share on other sites More sharing options...
Cloud Posted September 16, 2015 Author Share Posted September 16, 2015 I still havent bought an android phone to connect to an app, but since it got much colder in NY in the last 3 days, i havent had any tilt back incidents even during long rides. Would the voltage drop depend this much on the ambient temperature?? I still believe the tilt back was due to overheating and not voltage drop. Link to comment Share on other sites More sharing options...
SirGeraint Posted September 16, 2015 Share Posted September 16, 2015 Ambient temperature affected the overheating of my Ninebot One E+. I don't have the numbers in front of me at the moment but something like 93 degrees Fahrenheit outside I would overheat but around 87 degrees outside and I wouldn't. What was the ambient temperature when yours overheated?It seems like around 140 degrees (60 Celsius) is the threshold. I read where some manufacturer (maybe Gotway) raised there's from 60 Celsius to 70. I hope King Song is 70 as well.Can't you borrow an Android phone from someone so you don't have to buy one? Sometimes people have extras laying around. I know I've got 4 of them. Link to comment Share on other sites More sharing options...
Cloud Posted September 16, 2015 Author Share Posted September 16, 2015 I will now have to buy a new phone as i broke the screen on my current phone, so i will get an android phone. The ambient temperature was fluctuating around 75 to 80, maybe sometimes a bit higher and it was tilting back. Now the temperature is around 70 and it seems to be ok Link to comment Share on other sites More sharing options...
sylvere Posted September 17, 2015 Share Posted September 17, 2015 Can ask you what firmware do you have on your KS 800W ? thanks Link to comment Share on other sites More sharing options...
Cloud Posted September 17, 2015 Author Share Posted September 17, 2015 No idea about firmwareSomething else happened, the tilt backs came back. I am realizing now that they were related more to the riding style rather than the ambient temperature. When i accelerate and brake a lot, this happens. It could still be due to overheating. I am trying to find a momennt to go and get the new phone so i can finally check the temperature. Link to comment Share on other sites More sharing options...
Gimlet Posted September 17, 2015 Share Posted September 17, 2015 When you accelerate and brake a lot you are drawing a large currant from the battery which causes the voltage to drop simply because of the internal resistance. The power is there it just can't get out quickly enough. Link to comment Share on other sites More sharing options...
Cloud Posted September 17, 2015 Author Share Posted September 17, 2015 When you accelerate and brake a lot you are drawing a large currant from the battery which causes the voltage to drop simply because of the internal resistance. The power is there it just can't get out quickly enough.yes, i understand that this also supports the voltage drop scenario. But it also must cause the wheel to overheat. The pattern of when the next tiltback occurs after waiting a little, depending on how long you wait, appears to be consistent with what i would expect to see under the overheating scenario. When i get the temperature reading it should help clarify which is the correct reason. Link to comment Share on other sites More sharing options...
Cloud Posted September 20, 2015 Author Share Posted September 20, 2015 Ok i finally got an android phone and connected to the app. I am testing the unit now. Ive started with the aggressive type riding that always brings on the tilt back and in 5 minutes the tiltback happened. The temprature was 68.8. Voltage was fluctuating but around 60 to 62. I repeated 3 more times with approx same result. It starts tiltback when the temperature is approx 69 degrees. It only takes a few minutes of aggressive riding to get this condition.What will the experts say? Link to comment Share on other sites More sharing options...
Cloud Posted September 20, 2015 Author Share Posted September 20, 2015 Just tried again. 68.8 precisely is when tilt back startsin a few seconds, by the time i turn the wheel off, the app shows 69.5 Link to comment Share on other sites More sharing options...
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