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Old 06-08-2011, 12:36 AM   #511
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Quote:
Originally Posted by mini-dub View Post
Once the finish rpm has been reached the esc changes to top speed timing where it begins to add top speed timing based on the slew rate and maximum value selected. Slew rate is measured in deg/rpm, so it affects how quickly the timing is added. If the slew rate is 1*/1000rpm, it will only increase dynamic timing 1* every 1000rpm.
Ok, top speed still isn't completely crystal clear, so how about an example:

Start RPM = 5000
End RPM = 15000
Slew Rate is 1* /1000rpm
Top Speed max timing is 20*

Motor is currently at 16000 rpm.

Is the ESC adding 1* of timing or is the ESC adding 16* of timing ?

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It's a complicated algorithm, as are all boost functions..
Most boost functions aren't complicated if they make sense and are well-documented.

-Mike
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Old 06-08-2011, 12:58 PM   #512
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Quote:
Originally Posted by grippgoat View Post
Ok, top speed still isn't completely crystal clear, so how about an example:

Start RPM = 5000
End RPM = 15000
Slew Rate is 1* /1000rpm
Top Speed max timing is 20*

Motor is currently at 16000 rpm.

Is the ESC adding 1* of timing or is the ESC adding 16* of timing ?
I think I finally understand where you're confusion is stemming from. The slew rate is degrees added per 1000rpm. If the slew rate is 1*/1000rpm, it will add 1 additional degree every additional 1000rpm.

The slew rate is a slope - rise over run, not an equation based on the current motor rpm.

So going off your example, the esc will add 20* of timing total, but at 1*/1000rpm it will take a 20,000rpm increase to add 20* of timing.
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Old 06-08-2011, 12:58 PM   #513
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Attention 4s users on VTX10 and VTX10R esc's - we have become aware of an instability issue when running 4s voltage which has been the cause of some esc failure. We are working on the solution now that will be a very simple and easy fix to perform. If you plan to use your VTX10/10R esc on 4s please contact us toll free at 1.866.206.8558. This notice does not apply to 2s and 3s users. Thank you!
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Old 06-08-2011, 02:20 PM   #514
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Originally Posted by mini-dub View Post
I think I finally understand where you're confusion is stemming from. The slew rate is degrees added per 1000rpm. If the slew rate is 1*/1000rpm, it will add 1 additional degree every additional 1000rpm.

The slew rate is a slope - rise over run, not an equation based on the current motor rpm.

So going off your example, the esc will add 20* of timing total, but at 1*/1000rpm it will take a 20,000rpm increase to add 20* of timing.
Every 1000rpm from 0, or every 1000rpm from end rpm setting?

In the example above, is the esc adding 1* (1000rpm past end rpm setting), or is it adding 16* (16000rpm past 0).

-Mike
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Old 06-08-2011, 02:23 PM   #515
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The slew rate only applies to the top speed timing, which is why it's under the top speed timing menu. The top speed timing engages after the acceleration boost finish rpm has been reached.
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Old 06-08-2011, 04:21 PM   #516
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Quote:
Originally Posted by mini-dub View Post
The slew rate only applies to the top speed timing, which is why it's under the top speed timing menu. The top speed timing engages after the acceleration boost finish rpm has been reached.
Was there something unclear about my example? You still haven't answered the question, and I don't know how to ask it any more simply.

Can you just tell me 1 or 16?

-Mike
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Old 06-08-2011, 05:35 PM   #517
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Quote:
Originally Posted by grippgoat View Post
Every 1000rpm from 0, or every 1000rpm from end rpm setting?
Every 1000rpm after it reaches the end rpm value, because the slew rate only applies to the top speed timing which engages after the acceleration boost

Quote:
Originally Posted by grippgoat View Post
Was there something unclear about my example? You still haven't answered the question, and I don't know how to ask it any more simply.

Can you just tell me 1 or 16?
Neither 1 nor 16. If the max adv top speed timing value is set to 20* it will add a max of 20*.
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Old 06-08-2011, 05:49 PM   #518
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mike,
once the end rpm has been reached, the top speed timing is now active. lets say your end rpm is 12,000 rpm. if your slew rate is set for 1*/1,000 rpm this means at 13,000 rpm it adds 1* . and lets say your max top speed timing is set to 20*. this means that with your slew rate setting you will have 20* of timing added at the moment your motor hits 32,000 rpm.

acceleration boost timing is only to help get your car up to speed. once you are up to speed your top-speed settings take over to give you even more top speed for straightaways.. hope this makes sense.
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Old 06-08-2011, 06:01 PM   #519
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Quote:
Originally Posted by grippgoat View Post
Ok, top speed still isn't completely crystal clear, so how about an example:

Start RPM = 5000
End RPM = 15000
Slew Rate is 1* /1000rpm
Top Speed max timing is 20*

Motor is currently at 16000 rpm.

Is the ESC adding 1* of timing or is the ESC adding 16* of timing ?
It's a little difficult to be very exact going off this example because it's missing an acceleration boost timing value. The top speed and acceleration timing are separate adjustments, but they still work together.

In this example if the slew is 1*/1000rpm and the motor is 1000rpm past the finish rpm, the esc will have added 1* of dynamic top speed timing. The total amount of timing is dependent on the acceleration boost as well though.
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Old 06-08-2011, 06:58 PM   #520
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Quote:
Originally Posted by mini-dub View Post
It's a little difficult to be very exact going off this example because it's missing an acceleration boost timing value. The top speed and acceleration timing are separate adjustments, but they still work together.

In this example if the slew is 1*/1000rpm and the motor is 1000rpm past the finish rpm, the esc will have added 1* of dynamic top speed timing. The total amount of timing is dependent on the acceleration boost as well though.
I left the accelleration boost value out of my example on purpose, because from what you and Jeff had said previously (Jeff in person + PM's), it sounded like you were saying that you get EITHER acelleration OR top speed, not both at the same time.

So to try and summarize again:

From 0 rpm to Start RPM, you get motor timing.

From Start RPM to End RPM, you get motor timing + a percentage of accelleration boost.

From End RPM to infinity, you get motor timing + full accelleration boost + top speed timing equal to SlewRate * (CurrentRPM - EndRPM) / 1000.

So if accelleration boost in my example above was 20*, then at 16000 RPM, I'd get 21* from the ESC.

Is that correct?

-Mike
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Old 06-08-2011, 07:25 PM   #521
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Yep, sounds like you're getting the concepts now
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Old 06-08-2011, 08:59 PM   #522
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Originally Posted by mini-dub View Post
Yep, sounds like you're getting the concepts now
So, trying to clarify even more...

Start RPM = 5000
End RPM = 10000
Acceleration Boost Max Timing = 30*

Slew Rate = 5* / 1000rpm
Top Speed Max Timing = 40*

Then...
At 10000 rpm, I'll get 30* of added timing
At 11000 rpm, I'll get 35* of added timing
At 12000 rpm, I'll get 40* of added timing
At 13000 rpm, I'll still only get 40*, because I've hit the Top Speed Max Boost setting?


Then, what happens if I set as follows:
Start RPM = 5000
End RPM = 10000
Acceleration Boost Max Timing = 30*

Slew Rate = 1* / 1000rpm
Top Speed Max Timing = 0*

When I go beyond the End RPM, does the added timing drop back to 0, because that's my Top Speed Max Timing? Or does it stay at 30*, because that's my Acceleration Boost Max Timing?

-Mike
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Old 06-08-2011, 09:06 PM   #523
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The top speed timing will add on top of your acceleration boost timing.

If you have 30* acceleration boost and 0* top speed timing, when the end rpm is reached it will still keep 30* of dynamic timing to the motor.

The esc will only allow a maximum of 60* total dynamic timing, so if you have 30* acceleration boost and 40* top speed timing, it will add 30* for the acceleration boost, then add 30* using the top speed timing, but no more.
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Old 06-08-2011, 09:20 PM   #524
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Hey weylin, wanna say Thanks again for hooking us up with stuff for the sc race , u missed some good racing
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Old 06-09-2011, 08:29 PM   #525
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Going to try the Viper in my TC6 with a 10.5 and some boost...

Anyone got an FDR suggestion and ESC setting suggestion??
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