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[Alan Williams]

Apologies in advance for what might be a lengthy post but can anyone shed light on the following set of circumstances.


I have been using a spin99 pro opto with my Adverrun and Agenda since late last year. It was set up following the advice on here in much the same way as for my Hacker c50-13xl except for the timing and frequency and the brake. It worked fine EXCEPT that I had great trouble getting a decent throttle curve/response. 50% throttle was way too much power and speed despite reducing the ATV to 80% on the motor. I am sing a Futaba so for electric motors I used the motor function not the throttle.  I ended up with a throttle curve that at mid throttle was at about 30% power It was still a bit sensitive but I lived with it I have it set up so that when I plug the batteries in the esc will not arm until I press a switch which reduces the throttle trim to 0. The esc then gives one beep and is set to go.
Today I had a couple of flights as per usual. I then switched to a quick flip with a glow powered model.Then went back to the Agenda. I made silly error and left the transmitter on the wrong aircraft. When I connected the batteries the ESC gave a number of arming sort of noises. I realised my mistake, as it should not do this. Switched everything off and started again. ESC armed as normal with just one beep and  everything seemed fine BUT I had very low power on take off run. I had to push the throttle to 3/4 power to fly.
I landed and checked everything including the esc settings which were normal. Tried a different set of batteries. Same result. The aircraft flew just fine and had plenty of power but all in the wrong place on the stick. I checked that amp draw on the ground and it was around 90 at full throttle.
SO, I readjusted my throttle curve to 50% at mid stick, moved all the other points to what seems reasonable and everything is fine. In fact it is less sensative as I am using more of the available stick movment. So now I have what I would consider a more normal curve not one that is offset by -20%


Is it possible that I had not set up the esc properly to begin with and my problems with the throttle were due to this? When I caused the ESC to inadvertantly go beepy on me by powering up with a different model setting, did itreset itself to some sort of condition it should have been in in the first place?
I am mystified and any clues would be welcomed.


many thanks
Al.W

[Phil Lewis]

I don't know anything about the Spin as I don't use them but normally if the ESC see's some throttle on when powered up it would enter programming mode, and normally the first thing it does it learn where full throttle is then learn where zero throttle is when you pull the stick back.


Having said that you said you had reset the end points, in the TX or the ESC?


Phil

[Alan Williams]

Hi Phil,
on the spin99, I set fixed end points so that it goes by the pulse width to determine low end and top. Also the ability to program via the TX is switched. So I don't think it's that.

[AW2]

This may or may not be relevant, but:
Even with fixed end points, and with the ability to program with the TX switched OFF, if you accidentally have the throttle setting on the Tx a long way off the lowest point (where it normally arms the ESC) when you connect the motor battery to the spin 99, it will drastically alter the ESC settings.
It's never happened to me, but a very capable F3A flyer newish to electric power had problems with exactly this until we discovered the mistaken procedure.

[Phil Lewis]

Hi Al,


Are you saying you re set it again using fixed end points AFTER you mis-connected it or are you saying that was how it was how you originally programmed it? If the latter then as said above I would re-programme your end points again as it is likely that the ESC has re set them by letting it enter programming mode.


Phil

[Alan Williams]

Hi Phil,
the end points were set when I first set it up. They have not been changed. I checked them on the Jetibox following the change in circumstances and they are as originall set. I have  checked all the settings of the esc and they appear to be the same. I know it doesn't make sense but that is how things stand.
I discussed it with PeterJenkins and he summed it up like this "before the inadvertant use of the wrong model the throttle response was odd and seemed wrong but I could not change it. After the incident it is working as I would have expected."
I am just trying to understand what happened.

[Alan Williams]

In reply to AW2,
yes I guess I caused the spin99 to do something to the settings but I have no idea which ones and why the change remains in place even after flying it several times and not changing anything. I would have expected to see, via the Jeti box, one of the settings being different.
ah the mysteries of electrickery

[Keith Jackson]

Just to let you know that I have experienced the fixed end points on my spin 99 changing occasionally without me knowing if I'd done anything to facilitate this. So now I just keep a record of those and other ESC settings just in case

Keith

[Nigel Armstrong]

Is it possible to program the Spin 99 esc using a PC rather than a Jeti box? I know the Jeti Box works very well but it would be nice to be able to back up all the data in the esc.

[Alan Williams]

Thank you all for your input. I was able to double check that me settings ( in manual mode) on the Jeti Box were unaltered from those that I recorded when I first installed the 99 opto. I went to the field today and can confirm that the darned thing is working in the same manner as my last outing. That is after the "RESET" I have no idea why it was wrong in the firat place, nor why it reset. I can confirm that now it seems to be as I would have expected it to be in the first place as it is now set up with a throttle curve along the lines of those recommended by Malcombe et al. It is much more manageble. Just wish I had used the wrong model on it last year.

[AW2]

I've just re-read your first post, which includes
" [/size]I have it set up so that when I plug the batteries in the esc will not arm until I press a switch which reduces the throttle trim to 0. "
[/size]
[/size]In my experience, this is where my F3A electric beginner friend went wrong---if you have a big-ish difference between the low throttle position which arms the ESC, and the higher point on the throttle stick (or curve) where you connect the motor batteries, it can alter the ESC settings, even though you have manual settings with settings thro' RC switched off.
[/size]
[/size]Personally, I use two throttle curves, chosen on a two way switch.
[/size]They are identical, except at the very bottom, where one starts at 0, and arms the ESC and operates the brake.
[/size]The second one starts at whatever small increase above 0, will just hold the lowest idle rpm without stopping the motor.
[/size]I use this curve when flying if there's anything in the schedule which benefits from no brake.
[/size]But also it is used when connecting the motor batteries---and the very small difference between the two curves  has never affected the ESC settings.

[AW2]

Sorry about the previous post, dunno what happened there!
Can anyone make it readable?

[AW2]

In my experience, this is where my F3A electric beginner friend went wrong---if you have a big-ish difference between the low throttle position which arms the ESC, and the higher point on the throttle stick (or curve) where you connect the motor batteries, it can alter the ESC settings, even though you have manual settings with settings thro' RC switched off.

Personally, I use two throttle curves, chosen on a two way switch.
They are identical, except at the very bottom, where one starts at 0, and arms the ESC and operates the brake.
The second one starts at whatever small increase above 0, will just hold the lowest idle rpm without stopping the motor.
I use this curve when flying if there's anything in the schedule which benefits from no brake.
But also it is used when connecting the motor batteries---and the very small difference between the two curves  has never affected the ESC settings.

[Alan Williams]

AW2
Yes, I see that the ESC settings may be altered when the transmitter is on the wrong model, partcularly in my case where for my electric models I use the MOTOR funtion and for Glow I use the THROTTLE function. In the futaba they are very different functions, the motor function allowing for a motor cutoff rotary switch which is one of my saftey factors. I also use the momentry switch to reduce the trim on channel 3 to it's lowest position, at which point the motor is armed. It will not arm until that switch is activated. On the throttle function I assume that the low point is so high it will arm the motor. What is strange is that the spin normlly arms with one beep, when I used the wrong model it emmitted a series of beeps, none of which correspond to the manual. As I said I use the manual setting on the Jeti and on investigation NONE of these had been changed including the fixed end point values. So it seems that some parameter, that is not apparent on the Jeti box was changed. I had used this ESC before in another model, perhaps using the Auto Outrunner setting. Maybe it retained something from that setup despite reprogramming through the Jeti box.
Of course I could test this by using the wrong model on the transmitter and powering up the esc but I am a little fearful that it will cause it to revert to the previous setting, whatever that was, something I do not want to happen.