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Old 03-17-2010, 08:10 PM   #13351
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Originally Posted by CarbonJoe View Post
I think most of the use for dual mode is for modified motors, and maybe off-road. Since in dual mode (or complete sensorless mode), the ESC doesn't know the exact position of the rotor, it has to be a little less aggressive than it can be in pure sensored mode. Thus, it should be turning more RPM in sensored mode because the timing can be more precise as to when to apply power to the poles of the motor.
Good to know. I'll switch that out then and finish setting up the ESC. Thanks!
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Old 03-17-2010, 08:11 PM   #13352
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It was in dual mode. Is that the ticket then? I thought the advantage was doing Dual Mode, that way it kicks it into sensorless and increases the RPM on the top-end.
This may have been a more powerful option before the Vegas 2 software and v203 but with "Boost" and "Turbo" you can go far beyond the power of sensorless operation.
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Old 03-17-2010, 10:40 PM   #13353
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Originally Posted by CarbonJoe View Post
Is the Sensored Mode box checked, or Dual mode? Once you check the sensored mode box, you get timing boost. You can only select those in Hotwire.
The general rule is:
For motor greater or equal to 10.5R (17.5, 13.5), use sensored mode

For motor less than 10.5R (8.5, 5.5 etc..), use dual mode

However, I have tried sensored mode with 7.5R, and it can be tuned to be as fast as 5.5R. You just have to gear down, use less boost/turbo and watch the temperature.

Tekin RS pro gives you so much options on how you like to run your motor.
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Old 03-18-2010, 12:32 AM   #13354
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Is it possible to remove the solder post on the Tekin speedo and solder the wire directly to the solder pad? The reason I ask is because there are couple of time on my local tract the that wire got de-solder and burn the speedo. Need responce.
nope

the solder posts are the heatsink for the speedo
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Old 03-18-2010, 02:18 AM   #13355
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Examining the data logged on the track, I have found a weird problem.

Hopefully others have found it too and have some explanation.

Look at the portion where I have WOT (the longest, just after 146, that's second 14.6) and examine the RPM and current curves.
What could be causing those drops in RPM and current? That is the main straight on our track, and I am sure I have the throttle floored all the way. My turbo delay is .5 seconds.

Now the questions.
Is that drift in my radio which causes the Tekin speedy to not recognise full throttle and slows down? It sound impossible, since the throttle is still aplied (even if not at full) so why would it slow down? OK, let's say it's drag that slows down the motor a bit when the signal is not there to keep accelerating.

But then, .5 seconds later, turbo comes in (and it is very clearly defined), so the ESC must have been reading the WOT signal.

What is happening? Anyone? Randy?

I will do a recalibration today with the EPA turned down to 90% and then I'll crank them back up to 100% and see if that has any effect.

Later edit:

I bumped the EPA up 10%have and tried the car on the stand, and it doesn't show the same problem. Tested it on the road, the problem is still there. It is becoming clear however that I run out of boost about .1 second before the turbo cuts in.
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Tekin RS ESC sensored-data-log-shot.jpg  
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Old 03-18-2010, 04:34 AM   #13356
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my guess is that your begin RPM setting is put to high, getting too little timing and therefore loosing the current (and RPM). and/or your motor timing is too high.
im curious what it turns out to be!
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Old 03-18-2010, 05:13 AM   #13357
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my guess is that your begin RPM setting is put to high, getting too little timing and therefore loosing the current (and RPM). and/or your motor timing is too high.
im curious what it turns out to be!
A motor with no timing would accelerate slowly, that's all. There's no reason to drop RPM/current.

Not exactly sure what you mean by "losing current" in reference to the motor, but here's some detail.

The first thick horizontal line is at 8k rpm. My boost starts at 6kRPM (the first thin line below that). Motor timing is at zero (whatever that is on a SP V3, 17.5).
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Old 03-18-2010, 05:41 AM   #13358
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From my limited knowlege of the tekin and brushless in general , i thoughtthat the less timing on the motor the more torque it had ?? Thus accelerating harder out of the corners then the timing starts to come in and that produces the revs then the turbo gives even more revs
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Old 03-18-2010, 07:14 AM   #13359
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Originally Posted by niznai View Post
Examining the data logged on the track, I have found a weird problem.

Hopefully others have found it too and have some explanation.

Look at the portion where I have WOT (the longest, just after 146, that's second 14.6) and examine the RPM and current curves.
What could be causing those drops in RPM and current? That is the main straight on our track, and I am sure I have the throttle floored all the way. My turbo delay is .5 seconds.

Now the questions.
Is that drift in my radio which causes the Tekin speedy to not recognise full throttle and slows down? It sound impossible, since the throttle is still aplied (even if not at full) so why would it slow down? OK, let's say it's drag that slows down the motor a bit when the signal is not there to keep accelerating.

But then, .5 seconds later, turbo comes in (and it is very clearly defined), so the ESC must have been reading the WOT signal.

What is happening? Anyone? Randy?

I will do a recalibration today with the EPA turned down to 90% and then I'll crank them back up to 100% and see if that has any effect.

Later edit:

I bumped the EPA up 10%have and tried the car on the stand, and it doesn't show the same problem. Tested it on the road, the problem is still there. It is becoming clear however that I run out of boost about .1 second before the turbo cuts in.
i have seen this as well. first thing is lookat your throttle position. if you notice, the throttle floats at full throttle. it should be a straight line. the float is what will cause the tekin not to see full throttle. that is why you calibrate at less then 100% and then "bump" up your throttle response. it should eliminate that float in your graph.

to address the rpm drop off. I have seen it too. first thought was that I was adding timing too soon and the timing was reducing the torque to fast. so I did try changing gearing to eliminate that drop in rpm. it did not help. no matter what I tried, it was still there. I then thought it was wheel spin. that I was seeing the initial spike as the wheel spin and then the drop off was the tires hooking up again. but that was not the case that I could find. then I though it was the sentry just not able to read data fast enough. but I see this is almost the entire 8min. what I did notice was that at the very beggining of the run, that does not happen or it drops rpms less. what troubles me more is that my graph looks like that for a 17.5. then I looked at my 13.5 car and wow. I was seeing 3500-4000rpm drops. and they happen almost all the time. from min 1 thru min 8

my conclusion is that the speedo and motor is asking soo much from the battery, that the battery can not "pump" out enough to handle the load and that is why you see a dip. the problem is that a lipo is fairly stable on voltage, but when you pull alot of current very fast, the voltage seams to dip quite a bit. I am currently trying larger wire on the speedo to the motor and larger wire from the battery to speedo. and also adding more caps to the speedo. I have not "logged" any data since i made the change. I will try and get some log data this weekend and post up the resuts.

but you are not the only one. i have seen it in the 100s of logs that I have looked at. my feeling is that we see a power delivery limitation. just not sure where in the power system to resolve this yet. the other option is not running such an aggressive ramping of timing. I know i am the one that came up with the "short" rpm window and that realy does make the motor sing, but that maybe drawing current to fast. I have tried a wider rpm range and it seam to reduce this "rpm" drop off affect, but it does not eliminate it. it just delays it to further into the race.



looking at your graph some more. I generally do not see a "double" dip mine is usually just the single dip from the initial full throttle. i have not seen the second dip when the turbo kicks in. gotta think about what that would be
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Old 03-18-2010, 07:24 AM   #13360
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did you try gearing up (lower fdr) as well as gearing down ?
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Old 03-18-2010, 07:43 AM   #13361
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did you try gearing up (lower fdr) as well as gearing down ?
i would, but people already think I am crazy. I usually run like a 90-92mm roll for 17.5 1/12 where the "others" are in the 76-80mm range.
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Old 03-18-2010, 07:51 AM   #13362
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i am curious about this as well...i have raced at horsham in pennsylvania and some laps down the back stretch (17.5) the turbo would not kick in. with this being a small track, that speed on the back stretch can mean alot. what would cause this?




Also, how are the redline motors? im looking at picking up a second rs & 10.5 for my second car for my girl to join me in racing, and i was going to give her my older orion and take the redline if it is slightly better. Most of the people at my track run duo 2's, so i didnt know if it would be a better choice to buy the RS seperate with a different motor or get the combo..(please be fair and dont just say "omg get the tekin combo cause its made for each other")
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Old 03-18-2010, 08:08 AM   #13363
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Originally Posted by Swen View Post
This may have been a more powerful option before the Vegas 2 software and v203 but with "Boost" and "Turbo" you can go far beyond the power of sensorless operation.
Sounds good. It was my own oversight too as he listed on his setup that I was copying that he was in Sensored mode. Gotta pay attention to the details...
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Old 03-18-2010, 08:41 AM   #13364
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i would, but people already think I am crazy. I usually run like a 90-92mm roll for 17.5 1/12 where the "others" are in the 76-80mm range.
forget what people think if it works for you, then great !

the reason i ask is it sounds like what's happening is you're topping out and sort of hitting a limiter for the time when the rpm drops, then the turbo ramps up and you're away again with the extra timing.
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Old 03-18-2010, 08:58 AM   #13365
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Originally Posted by chris_dono View Post
forget what people think if it works for you, then great !

the reason i ask is it sounds like what's happening is you're topping out and sort of hitting a limiter for the time when the rpm drops, then the turbo ramps up and you're away again with the extra timing.
that is what I am thinking when you see the couple of "double" dips in the graph that was posted. I don't see that in my setup. the only dip i see is when I first hit full throttle. I know I am not maxing out because just before that point, I have no timing added and my start rpm is 4000-4500 for 17.5. after i hit full throttle, the rpm just get to about 5000-5300 before it dips. my end rpm is 6800 and I add 50 degrees of timing. so i am adding ~18 degrees per 1000rpm. so i would only be at 18 or so degree. that should not be overtimed at that point in the motor. my turbo delay is .6, so turbo would not be kicking in either.
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