Thanks for the reply Adrian

What About a Power Capacitor ? is it needed.
And for a 540 motor, is it best to run ENSA , or no ENSA , i need al possible juice to these weak motors..

No power caps are not needed. The Keyence not like any other speedo. There is a lot more going on in it than you think.

I have run mine out of the box with no schottky or power cap on everything from 540's in Minis to 7 turns Mod Sedans.

I run the Keyence Zero Extreme and also use no power caps or any type of diodes with and it works flawlessly. Been an excellent speedo for me with great durability. Hell I even hooked it up and backwards and damn if that thing didn't still work after I hooked it up the right way. I don't reccemmend that but I was very happy it didn't burn up.

I'm running the Rapida Pro and it is awesome..I highly recommend!

Guys,
Will the drive frequency have any bearing on the power-band of a motor (7x1)? Will there be a slight increase in the power of the motor at top-end (extra speed)?

Regards,
Peter :D

the rule of thumb is the lower the number the lower the power band....IE more low end (not less overall power) and the higher the number the higher the power band. Keep in mind low numbers heat up the com...high numbers heat up the Speed control. I generally run 1.5 for stock. 2.0 for 19 and around 4 for mod.

can the zero v extreme be used in 1/12th 4 cell mod, without any capacitors or schottky diodes or whatsoever? thanks.

Same here.

The way that it was explained to me...

Think of the frequency as a flight of stairs between the bottom floor (foot off the gas) and the top floor (full power). The higher the frequency, the more steps on the stairs between 0% power and 100% power.

Now with a lower frequency, there are less steps for the ESC to take between off throttle and full throttle.the car *feels* punchier. However, the power of the motor has not actually increased. Basically, a lower frequency speeds up the motors reaction as you change the amount of throttle input on the transmitter trigger. This provides less work for the ESC to do and therefore it runs cooler. But this also puts more stress on the motors comm and can cause excessive arcing, higher motor temps and power fade. More frequent brush cuts will also be needed.

Now with a higher frequency, there are more steps for the ESC to take. The car may *feel* less punchy, but the truth is it gives you more precise throttle control. This is the reason why the lower the turn motor, the higher drivers run the frequency. If they didn't, the car would be hard to handle due to abrupt changes in torque to the wheels. More kHz means more throttle control. Now the ESC has more work to do and therefore it runs hotter. On the other hand, the motors comm will last longer, it will run cooler and the power will be more consistent within a run and between runs.

Personally with 19t motors I tried running 1.5, 2.0, 2.5 and 3.0kHz (more in the standard low turn mod range). At 2.5 the comm had almost no black streaks from arcing and at 3.0 I saw a marked improvement in consistent lap times (probably due to better driving lines coming out of corners from the increased throttle control), as well as motor life.

Wow, tnx, you explained it well. good analogy too.

Does anyone here run a Rapida or Rapida Pro with the Spektrum receiver? Do you have any BEC issues, or is pretty much plug and play?

That is incorrect.

You are describing the number of throttle steps, which on most esc's is a fixed number. That is the value which determines the gradition of throttle control.

Drive Frequency describes duration of the on and off periods of the throttle duty cycle. ESC's output pulse width modulation, not linear DC power. When you vary your throttle, you are only varying the duration of output during the "on" state of the throttle duty cycle. Full throttle, the esc outputs power for the entirety of the on segment of the throttle duty cycle, half throttle throttle the esc will only output power for half of the "on" stage of the throttle duty cycle.

I'm glad someone who actually knows electronics could tell me the truth. :nod:

However, regardless of what is actually going on electronically, I will say that I indeed saw the above mentioned changes in throttle control feel, lap times, ESC temp, motor temp and comm life.

Now, please explain what you just said in a manner to where those of us who don't know what an 'on segment' or 'duty cycle' is can understand. And why did I see the changes mentioned above when going from a lower frequency to a higher one. :D

Your impressions of feel, temp and comm temperature are correct.

At full power you are cranking all the voltage and current the esc/battery combo can toss out for the duration of the on cycle. The lower the frequency the longer the output of juice each cycle. As rc legal motors are limited to 3 poles, each segment is exposed to current for a relatively long time in the first place (most industrial applications have motors that are 5 poles and greater). A low drive freq produces more punch but more heat as each segment is exposed to a more sustained blast of current.

Ahh. Thanks! :)