Kontronik 65% throttle curve?

[jmb2232]

OverTemp and MrMel, I salute you both! Thanks for this explanation. I understand the relationship now and actually will sleep a little better tonight. Sad I know, but true.

Michael B.

[NRPY]

Yeah, great post, OverTemp! Makes sense when you break it down like that.

[mmarian]

But we still do not know at what point of the uncalibrated or calibrated radio throttle curve we reach 100% of power outpout from the Jive ESC. We need to know this in order to leave about 15% capacity or head room to allow the governor mode to operate properly.

[MrMel]

Originally Posted by mmarian

But we still do not know at what point of the uncalibrated or calibrated radio throttle curve we reach 100% of power outpout from the Jive ESC. We need to know this in order to leave about 15% capacity or head room to allow the governor mode to operate properly.

Yes you do,

to see actual PWM out, No you need Jlog for that, but to have 15% throttle in headroom is as simple as
Calibrated 100% - 15% = 85% then you can use above formula to calculate where that puts you without calibration if you want that.

[OverTemp]

Comes out to 78.7%

[mmarian]

So, this whole discussion was a mere storm in the tee cup after all . For everyone using calibrated throttle channel - having the ATVs set accordingly ( in my case at 82 high and low end point on Spektrum DX7 ) I can safely set my flat throttle curve up to 85% and still have enough head room for governor, right ?? And this maximum 65% only applies to people who did not do the calibration, as per Mr.Mel video, right ?? So, where the 78.7% fits into all of this ???

[MrMel]

Correct!

But there is of course more layers to the onion, to make sure for certain that you have enough headroom, you need Tom's JLog and watch the PWM out to make sure it does not hit 100% too much.

(then all things comes into play, temp, battery etc)

[OverTemp]

78.7 on a non cal radio equals 85 on a cal radio... That's all.

Storm in a teacup... Funny... I like it

[mmarian]

In part this discussion has been prompted by another thread called Governor Headroom where contributor "Stolla" claimed that anything above 65% throttle flat line is bad because there would be no headroom left for governor and anything above 80 is running Jive ESC constantly or most of the time at 100% power output. That confused me and I guess many other readers on this forum. So, conclusion of this is that if we have a calibrated throttle channel in our Tx, we can get full benefit of the governor mode having the throttle curve - flat line up to 80-85% and between 70-78% on uncalibrated radio. That is a good news, since the original claims (by Stolla) seem to be not completely true or accurate ... At least hat is the conclusion I am taking out of all of this interesting discussion.

[OverTemp]

Personally, and this is founded only be intuition, I think people are too big pinion and headroom happy. I prefer the cooler running setup with a slightly smaller pinion and about 75-80 on the curve... my 7HV flies great on 64/71/80/84 curves with a 13T pinion on a 520 kV motor. The 80 and 84 work fine, power is sick. Seems everyone else is running 14T and 15T. Thats a 15% reduction on torque and increase in heat in the name of headroom for PWM. I have no problem with my ESC going full power now and again. That's when they are supposed to be most efficient, or at least used to be until this JLOG and it's graphs came out.

[MrMel]

OverTemp is correct, now you come into if the overall system is on the 'insanely powerful' or weak category, weak system need more headroom

[mmarian]

I think people are too big pinion and headroom happy.

That was the impression I was getting out of the Governor Headroom thread. It invoked that it is better to have bigger pinion and lower throttle curve in order to have enough head room for the governor than the other way round which contradicts my own experience. I think that people were mislead into believing that running throttle curve above 65% is wrong. Anyway, as many people as many opinions, I guess. I am sticking to what I have been doing for long time without any adverse issues. I am glad that this whole headroom, throttle curve, calibration with ATVs has been thoroughly examined and explained for all of us to understand.

[dl7uae]

I am glad that this whole headroom, throttle curve, calibration with ATVs has been thoroughly examined and explained for all of us to understand.

Sounds like a joke to me. I w'd call it a bigger misunderstanding than before.

Well done...

[OverTemp]

How about you post something constructive rather that a smart a$$ comment.

[Chris_M]

Personally i have never been able to run much over 70% curve on calibrated tx (-82 +82) on any of the Jives I have without topping out at 100% for the last minute of flight. I understand its relative to many variables but I have proven this through Jlog. I am not talking about peaking out at 100 every now and then but using full power for almost the last minute. And with the variable voltages, motors, flight style and other amp pulls on the system I dont understand how you can give an actual number of 78.7%. I dont think people are headroom happy but if you can put a heli through its paces you need a buffer and theres no way around it especially with high kw motors. And what may work for one may not work for another. One heli being sport flown with a 700MX at 70% curve can not be compared to another flying smack with a Scorpion LE at 70%....its all relative.

[smsodhi]

It seems such a shame that Kontronik do not allow us to program the speed controllers via a computer like the CC ESC or the Vbar gov, and the sofware should then take care of all the uncertainty. This is all mind bending.
I have just bought a decent tach so that I have an idea of what HS I am running. I should be able to do this through the software like CC or the Vbar gov.
I have helijives and from what I understand the end points should be left at 100 100 so there is no calibration? yet at throttle curve of 80% the esc was maxing out and bogging. On lowering it to 65 all is good.

[NRPY]

I don't think setting the desired RPM via a software GUI according to assumed parameters (which have tolerances themselves) is really any better. You still should verify the finished product with a tach. No way around it if you want to be sure.

I find all this throttle % talk to be confusing enough to not really place much faith in it. So I've ordered a JLog2. I'm going to let the data speak for itself. Problem is it apparently takes about 4 weeks to ship from Deutschland.

[mmarian]

Originally Posted by Chris_M

Personally i have never been able to run much over 70% curve on calibrated tx (-82 +82) on any of the Jives I have without topping out at 100% for the last minute of flight. I understand its relative to many variables but I have proven this through Jlog. I am not talking about peaking out at 100 every now and then but using full power for almost the last minute. And with the variable voltages, motors, flight style and other amp pulls on the system I dont understand how you can give an actual number of 78.7%. I dont think people are headroom happy but if you can put a heli through its paces you need a buffer and theres no way around it especially with high kw motors. And what may work for one may not work for another. One heli being sport flown with a 700MX at 70% curve can not be compared to another flying smack with a Scorpion LE at 70%....its all relative.

I think there that there is another think to consider in here. By gearing up the system (using a bigger pinion) in order to increase the HS with lower TC (below 70%) and thus have the head room for governor could be actually counterproductive because you actually putting more stress and demand on the power and that could be one of the reason why your ESC is maxed up for the entire last minute of each flight. By having smaller pinion and higher TC percentage the system runs more efficiently and it is less power hungry and hence needs less headroom to cope with the changing power demand.. I guess it would be worth trying on your power hungry helicopter and see what the JLog would say with smaller pinion and higher TC %. Of course it all depends of the style you fly, the way the heli is set up mechanically etc. etc. My friend's heli is mechanically so "tight" (lot's of friction in moving parts) that the blades are hard to spin by hand. His flight times are 20% shorter on the same heli and the same electrical components than mine. My blades keep spinning forever when I spin the blades on the ground by hand - minimum friction on all moving parts. So, I guess this is a quest for finding the sweet spot between making the heli to perform on one hand and operate in the most efficient margin on the other. I suppose we all do things a bit differently but at the end of the day we just want to enjoy this hobby and get the best we can at it.

[OverTemp]

Originally Posted by Chris_M

Personally i have never been able to run much over 70% curve on calibrated tx (-82 +82) on any of the Jives I have without topping out at 100% for the last minute of flight. I understand its relative to many variables but I have proven this through Jlog. I am not talking about peaking out at 100 every now and then but using full power for almost the last minute. And with the variable voltages, motors, flight style and other amp pulls on the system I dont understand how you can give an actual number of 78.7%. I dont think people are headroom happy but if you can put a heli through its paces you need a buffer and theres no way around it especially with high kw motors. And what may work for one may not work for another. One heli being sport flown with a 700MX at 70% curve can not be compared to another flying smack with a Scorpion LE at 70%....its all relative.

I was just stating that 78.7 equals 85 in that post. Mr Mel said you can convert it, I just converted it.

I think 85 is just a touch too high for my particular battery motor combo on one of my helis, but not on another (well, closer to 82-83 works better actually). I have no issues on either around 80 (.75 uncal). Like Mr Mel said, not black and white. Depends on motor power vs model size/RPM/pitch. If you are eating up most of your headroom at the biggining of the flight because your motor is weak, or course you are going to max out and bog at the end. If your motor HS excess power available and all the extra headroom isn't being used, then you can afford to run a higher throttle percent and a smaller pinion, further increasing your torque and reducing current.

In short, there is a sweet spot for each combo. I just don't think it's right to start out over geared. Start smaller and work up if you have to. My opinion.

[Chris_M]

Originally Posted by mmarian

I think there that there is another think to consider in here. By gearing up the system (using a bigger pinion) in order to increase the HS with lower TC (below 70%) and thus have the head room for governor could be actually counterproductive because you actually putting more stress and demand on the power and that could be one of the reason why your ESC is maxed up for the entire last minute of each flight. By having smaller pinion and higher TC percentage the system runs more efficiently and it is less power hungry and hence needs less headroom to cope with the changing power demand.. I guess it would be worth trying on your power hungry helicopter and see what the JLog would say with smaller pinion and higher TC %. Of course it all depends of the style you fly, the way the heli is set up mechanically etc. etc. My friend's heli is mechanically so "tight" (lot's of friction in moving parts) that the blades are hard to spin by hand. His flight times are 20% shorter on the same heli and the same electrical components than mine. My blades keep spinning forever when I spin the blades on the ground by hand - minimum friction on all moving parts. So, I guess this is a quest for finding the sweet spot between making the heli to perform on one hand and operate in the most efficient margin on the other. I suppose we all do things a bit differently but at the end of the day we just want to enjoy this hobby and get the best we can at it.

The example I gave was running a smaller pinion and only maxed out PWM in IU2 but still at 70%. Like others have mentioned a Jlog is the best tool to find out exactly how your system is running. I wouldn't put the efficiency of the system on calculations or guess work. Motors don't always run at advertised kv and lipo discharge can vary and I would suggest to everyone who has a jive to get a Jlog. You will sometimes be surprised with what you find