Worlds Best ESC - Making it Better

That's a bold statement ... Worlds Best. But it's even larger than that. Not just Worlds Best, but best for most all applications less than 30 Amps (limit of the tests). That means:

- duration ships that only pull 2 to 8 amps per rotor

- most all 6S and smaller ships (exception of nano-ships)

- any-size FPV racer

- any other ship in between

Why almost any size? Shouldn't a small FPV racer use a smaller and lighter ESC for response? Yes, if it does better on a net-lift response test. In other words, when you penalize the ESC for it's weight, is it still better and faster? What i continue to see is ESC manufacturers downsizing critical components of the ESC at a net loss. They weight savings is lost because of greater thrust loss and response. In other words, this heavier ESC will out accelerate, in the real world, a smaller and lighter ESC.

Why post this? To move technology forward, we need to report to industry what works and what doesn't. For some reason (i don't know why), this ESC works better than all others tested:

- for generating maximum thrust from the motor***

- for net-lift efficiency or the grams of weight it can lift (after it lifts the rotor) per watt

- for response (how fast it can generate targeted lift)

These tests were conducted on multiple days on multiple rotors of highly variant size, always being immediately compared back to another DYS 40A multicopter test to ensure that the baseline wasn't changing.

The ESC that dominated is a DYS 40A OPTO Multicopter using SimonK. The photo is included because there are two others that carry a similar or same name.

- Not the white cover DYS BLHeli 40A

- Not the one that is says "Programmable" versus "Multicopter" in the blue/purple band across the front


Have i tested all ESCs? No, but if you are convinced you know of one that would work better, let me know. I've tested most all of the following and one or more of their variants:


- Multistar

- Turnigy

- T-Motor

- Afro

- Motortron

- Quattro

- 3DR

- Spider



- Aris


- AutoQuad

- Exceed

- HobbyWing

- Lumenier

To do a test like this, a highly repeatable and finite test stand is needed. It took a while to develop one but what works is one that:

- measures (at a minimum) volts, amps, thrust, motor temp (shoots IR up the aft end of the motor)

- eliminates harmonics between the rotor and load sensor (this proved difficult but achievable)

- is calibrated and proves repeatable within 1.5%

- controlled by a system that can precisely repeat a rotor test (uses a Audurino Mega)

- directly feeds the data into Excel for analysis (uses DATAQ)

- uses a test script that produces repeatable results

- uses a test procedure that minimizes repeatability error (used average of multiple tests)

How much better is this ESC?  On average:

- 4.4% higher net lift (after it lifts itself)

- 2.3% more net-lift efficient (usually the larger the better)

- from more than twice the response or the same response as other ESCs (usually the larger the better)

                                                       So how to make it better?

Step 1: Strip it naked. See photo below.

           ... remove the cover

           ... remove the heat plate (better to locate the ESC under prop wash to run cooler, see below)


Step 2: Right-Size the bullet connectors or wires (see above where heavy wires are replaced by 2mm bullets)

           ... remove the large bullet connectors or wires

           ... replace them with ones that are the most net-lift efficient (where heat loss = weight loss)

Step 3: Seal the ESC. Seal it with Electrical Sealant to protect from moisture and conductive dust

           ... tape or plug connectors and wires

           ... repeatedly spray each side from different angles

           ... a mistake i made was not sealing the bullet connectors and solder

               - don't tape them off like i did

               - insert a male connector into the end of bullets so sealant doesn't get inside them


Step 4: Locate ESCs under Prop Wash. See photos below. The turbulence generated by the prop does not adversely affect lift when the ESC is placed on edge to the prop wash.

           ... Use something non-conductive like hot glue to bond the ESCs to the motor mast or spar

           ... Face the FETS (the little square warehouses or Fire Emitting Transistors) to open air

           ... Protect the ESCs from below from ground contact (not needed here because of clearance)

back-side with hot glue


front-side with FETs completely exposed to open prop wash


Step 5: Tie up wiring. Use dental floss to secure wiring away from the prop.

***Note: The T-motor Air 40 in high-timing mode (an option) generated higher thrust, but at the sacrifice of efficiency and motor temp. Also, the T-Motor Air 40 was 2nd best and close in performance. If you are using an Air40, it probably isn't worth switching.

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    • MR60

      ... and to my surprise, the toggle in software produces a measurable difference  between efficiency and "sport" mode. It's a mighty fine ESC.

  • At this RCGroups thread people also seem to like these ESCs -->

    • MR60

      looked at their test. You can see why many pilots are taken in by marketing. Most pilots don't have the $$$ to buy the necessary equipment nor do they desire to take valuable time away from fun FPV flying to create metrics we can use. Instead they do the "Charmin" test. I do that test myself and it is a good way to discern large differences between products.

      • Mr. Frantz.

        Since you believe in the F330 ability in the dys40 why don't you take all of your above information on your work and post it here and see what these people think of your hard work. I am shure they will find it most interesting.

        • MR60

          My message to ESC designers and manufactures is this ...

               A good coach focuses on fundamentals first. Once optimal, then the coach adds smart play.

          My message to FPV racers is this ...

                                                     Ignore the hype. Focus on results.

          I will take your advice. But at the moment, teaching takes 2nd fiddle to testing and finding a method for pilots to reach that data. The only way to teach a FPV champion, is to beat him with a ship built by thorough testing. Then and only then do they listen.

          • You said it well. Ignore the HYPE. Focus on the results.  You are giving us alot of hype but you have yet to produce any legit concrete results. The racers are seeing the results in real time at races. Now I challenge you to beat the FPV Champs. Like you said. Post your info on the above link.

            I am now signing out of this going nowhere discussion.

            • Finally! Thank you!
    • I LOVE the SN20A; it is the same ESC as the BL20A, only with outdated SK firmware. We buy them when they go on sale and flash BLHeli on them to turn them into serviceable entry-level acro ESCs. :D



      • MR60

        for anyone that wants, mail me an ESC. Friend me so i can send you my address. tell me if you want the comparison results published or private. 

  • Forrest, with all due respect... you have no idea what you're talking about, at least where racing is concerned. Those DYS aren't even in the top 50 for a racing ESC; they're ancient tech with crap FETs that switch too slow and have way too high  on-resistance. A real racer wouldn't even CONSIDER them, they're what we'd call a "boat anchor".

    Today's cutting edge ESCs are running faster 32-bit processors than the FC in your quad, and they have to because of the speed and demands for twitch-trigger responsiveness that racing quads and acro pilots demand. The FETs have such low on-resistance they have to have dedicated drivers, and we consider active braking to be a minimum requirement, NOT an option.

    You're putting this kludged-together airplane ESC up as a paragon of ESC performance, when I binned ESCs that outperform them on their best day years ago.

    We're running excess of 30K RPM nowadays dude... that needs a lot smarter, stronger, and faster ESC than any Atmel-based processor can deliver, and certainly that finds even the latest SK firmware sorely lacking.

    Oh, and we use velcro wire wrap to keep our wires out of trouble. ;)

    *Toddles off to ded*

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