Joined Feb 2013
Test review DJI E800 Tuned Propulsion : Sinewave (R) evolution of the middle class?
Test review DJI E800 Tuned Propulsion system: Sinewave (R) evolution of the middle class?
Anyone still wondering in 2014 about the success DJI has had with the E300 / E600 Tuned Propulsion Kits, realized pretty soon, that this was only the beginning of the story. In 2015, the DJI Tuned Propulsion program (meanwhile copied by several competitors) has been completely renewed and extended with E310, E800, E1200. DJI covers all common sizes for Multicopter mass market now.
Sounds like business as usual. Most companies are changing some details, size or color, or realize program extension by upscaling. Emphasis on product refinements and improvements, taking care for the details of existing designs, is the standard way to go, but boring as well.
But DJI did something very different this year....They extended their propulsion program by a completely new product line, serving new RTF line of the company as well. Inspire I1 and recently the Phantom 3 drive train have been part of this development.
New Motors with perfect coils (Single strand wired) and ESC, supplying them with sinusoidal power are representing a true revolutionairy design change in the segment of small and mid size Multirotors. Although this technology has been already part of rather sophisticated industrial applications and better EV, it was probably too expensive or too complicated for the RC mass market and its manufacturers... until DJI came up with it. Tempi Passati, trapezoid.
So it does not surprise that the DJI motor development team puts its label DJI Propulsion Lab on the products, getting into the light of the public. An additional Created in China is shouting out the new self-confidence of a department, which seemed to be limited in the past, contributing parts for RTF Multirotors or kits. This obviously changed with the introduction of the E300/E600 propulsion kits on RCGroups, when the DJI Propulsion team started to discuss with their customers, spreading some insider news as well, far away from usual marketing twaddle.
The following E800 review wants to check , if the new self confidence of the DJI Propulsion Lab is justified.. Did they do a good job?
Bye Bye Bulk: The E800 Tuned Propulsion package (here the Quad rotor kit with 4 pcs. 20A controllers/3510-350KV motors) is coming in a kind gift packing: Motors and controllers as well as USB interface, are coming with carefully folded cables, softly embedded, the bottom of the package contains the tool box. 8 rotors come loosely packed, stored in a separate cardboard.
The tool box with DJI Logo looks like a nice gift for a multirotor party, it contains everything needed for a complete assembly:
Screws: 30 pcs. M3x4.9x6.8, 30 ea. M3x5.5x4.5, 30 pcs. M2.5x5x1.2x1, nickel plated and with thread locker coat.
Heat shrink tubes : 10 pcs. red and 10 pcs. black in 5x20mm. For battery /coax cable ?
Distribution board: Optimized for the 620S coaxial cable. Remarkable small. Wow.
Hex key: 1 pc. M2, good quality
3M Tape: 4 pcs. for ESC mount
Fork wrench: Its purpose is to grab the motor (DJI 2312 and 3510) for self tightening rotor removal. Its not really needed for the 1345 attached to Quick Release Rotor Adapter.
Magnet in the cover: Well-meant , but keep it away from Compass sensors.
No more thread, no more centering .
The E800 1345 rotor (13x4.5), Z-Blade shape, has been designed for the E800 Tuned Propulsion kit: The goals were efficiency and low noise. In addition to that, high manufacturing quality is supposed to insure that there is no need for balancing anymore. And it seems to be like that: A quick n dirty static DIY balancer did not show anything to worry about. This is important, since the idea of this kit is Plug n Fly, out of the box. Btw. Rotor replacements are surprisingly cheap.
Their weight is only 19g and they are coming with a glossy mold finish. Well made. Their hub (if one would like to call this a hub) is completely new, some sort of push 'n turn attachment, called Quick Release Rotor Adapter: Press down… turn. Like a safety device for children. Inspire I1 customers know this solution as supplement, recommended, since their ESC are also coming with Active Braking (this protects them from coming loose) However, it is still possible to attach the 1242 rotors of the E600 kit. This bears some risks, if the the rotors aren´t carefully attached, but friends of heavily loaded F450 will ignore this anyways.
Yes we can. Its possible to mount to mount other rotors besides 1345 and 1242. Once the Ф22 Quick Release Rotor Adapters are removed, its possible to attach rotors with 4 hole 12mm distance mount. Y-6 and other coaxial multirotor design fans will appreciate this.
E800 620S ESC
Fits great 620S ESC meets Tarot style motor mounts. Btw., the internal LED indicator of the 620S ESC mirrors the external one.
Plug n Play, just the coaxial supply needs soldering.
The 620S ESC (rating 20A, 3-6S LIPO), are the real novelity of the E800 Tuned Propulsion kit .First of its kind for mid sized multi rotors, worldwide. They are coming with more computing power than some Flight Controllers. Much effort, what for ? They offer, for the first time in its class, sinusoidal control of the motors, health monitoring, an active braking system, external LED control, a data interface, providing easy access to firmware updates and other features. Integrated spark proof protection as well !
The DJI assistant software has been done for beginners, it is self-explanatory.
S symbolizes sine wave: Since the DJI Propulsion LAB had all the effort it took to create this novelity, it was logical to ask them for a statement about the advantages:
1. There are 2 types of 'ideal' motors. One has a trapezoidal shaped back EMF, the other has a sinusoidal shaped back EMF. For most RC model applications, motors are very close to the ideal sinusoidal case. Therefore, driving the sine-wave motor with trapezoidal current is very inefficient since the current harmonics does not generate average torque (the word average indicates that the torque does work). And this is why sine-wave drive is more efficient, and that is equivalent of saying it'll be cooler since less energy is converted to thermal energy.
2. Why is sine-wave drive motor smoother? One reason is the control algorithm is better and more sophisticated so that the commutation is under better control than a traditional BLDC drive. The other reason is that current harmonics generate torque but not 'average torque', technically it is called 'torque ripple', you can consider it equivalently as the cogging torque. Torque ripple is reduced by reducing current harmonics.
Well, this is rather an answer for motor experts. Short summary: Smoother run, higher effiency, lower temperatures. And yes, the test revealed some of it outside the laboratory as well. Particulary its outstanding response, and the lower noise level are for sure part of the new technology. DJI users won´t miss neither SimonK nor BLHeli. Not at all.
Great: The power leads are realized with a very slim, flexible coaxial cable (Side effect: Better EMC and more lower static magnetic interference) No more twisting. Together with the included, tiny ( low interference) distribution board, a perfect power assembly is no miracle anymore. Nice.
Long, long, long . The 620s ESC are coming with very servo/supply cables (44/42,5cm), sure meeting the requirements of most builders. Good bye, extensions ! Well, longer is better.
With a size of 74x32x10.5mm the 620S ESC are just as large as the 420S ESC of the E310 Tuned Propulsion kit, since the same plastic housing is used. This provides perfect protection for the internals, all the connectors (Motor, LED , USB Data port) and last not least for the two Low ESR capacitors. Both sides of the housing are flat, so its easy to mount them without any distance, zip tie use won´t do any damage (e.g. internal shorts), sticker can be used for a durable fix. Their weight of app. 43g includes the very long coax and servo cable.The overall impression is: Solid as a rock, bye bye heatshrink tube.
E800 3510/350KV Motors
The 3510 motors (3510-350KV), 109g, 18AWG wires are coming flat black, first-class finish. Mainly this due to the single strand wiring: Perfect wounded coils with stronger wires lead to some sort of strength and durability impression. Side by side, other motors look like cheaply handmade products. This will hurt the cloners. Btw. the DJI 3510 are coming with NMB bearings. Brand new production plant. No 3rd party impacts.
By the way, the axis is coming with a M5 R/L thread. Attachment thread distances are providing commercial standards 16x19x25mm (M3)
Visible perfection Single Strand Wiring, Surface finish.
Test Thrust vs. Power Consumption
For first drive train tests (weather independend), its always a good idea to check the Thrust versus Power Consumption. Great for relative comparison, not that great for absolute accuracy. Nevertheless, although real life is different (some impacts are missing), the results came amazingly close to reality.
Test procedure The E800 drive train (ESC/motor/prop) pushes (at least 50sec) with a lever onto a scale, which is displaying the related thrust (600,800,1000g). At the same time, a wireless logging system is monitoring and storing Voltage, Current, Power, Time. In order to minimize errors: Repeated measurements with new 6s/5200mAh batteries of the same production batch..
Test results :
Power Consumption at 600g thrust 55--58 Watt (24V/ 2,4A)
Power Consumption at 800g thrust : 84-87 Watt (24V/ 3,6A)
Power Consumption at 1000g thrust 114-117W (24V /4,8A)
Explanation: Thrust vs. Power Consumption Scenario :
The charts are showing the power consumption of one drive train, that means for a Quad current and /or power must be multiplied by 4, for Hexacopters by 6, for octocopters by 8. For total consumption, Flight Controller, and all the other accessories, like e.g. GoPro, Gimbal, FPV transmitter, LED have to be added as well (e.g. NAZA 5W, ZENMUSE up to 8W....)
Battery choice : A 6s 6000mAh battery labeled with 20C is designed to supply 120A continously. The C-rating is important, burst or peak ratings (usually the second, higher number e.g. 20/40C) should be ignored.
Example: With 800g/Axis a Quad with E800 needs about 16A nom. @6s for motors and ESC. If one adds the current for the remaining components (e.g. Flight Controller) and all the extras (such as FPV gear, LED chains..) plus 20% for safety, even an (honest!) 20c rating (120A) for a 6000mAh battery would be more than sufficient. But experienced builders know, that these ratings usually are not pretty honest, so that its not a bad idea to divide them by two, if cheap batteries are used. And its a good idea to ignore fancy burst or peak ratings. Nevertheless most builders using better brands will get along with 30C ratings, stunt flyers go for the best they can get, if not too heavy and expensive as well;-)
If 5s or 4s batteries are used, the currents are higher at same Power Consumption. Power requirements are about equal, but P = U x I (Power = Voltage x Current) remains valid.
Note: Above-mentioned values were determined conscientiously and also in repetition, but we are not talking about science here.
Since some of the competitors are coming with 40A labeled ESC, it appears, as if the 620S ESC are far too weak, born to get fried. But there is no reason to worry, not at all, since the 3510 motors get along with 13.5A (@6s) at Full Throttle (App. 1800g thrust!!!). At 1000g thrust, the current doesn´t go above 5.4A. At 800g thrust we are talking about 3.8A, so even an honest 10A rating of the ESC would offer more than enough. Btw. , according to P=U x I the 20A rating at 6s (22.2V) equals 444Watts !
Set-up with E800 Tuned Propulsion
All inclusive. This kit is complete as usual. Like the other DJI Tuned Propulsion sets, the E800 provides everything needed for a successful setup, including a hex tool. The tool box provides parts for various frame assemblies. The motors with 16x19x25mm M3 holes can be screwed onto all standard motor mounts .
Included as well. The very small power distribution board has been designed for the coaxial power cables of the E (S) series. Up to Hexa config. For an Octocopter its probably better to use two of them, face to face. Its small size also helps to reduce EMC fields (with negative impact on sensors.)Soldering is pretty easy, no flux required at golden contact plates. If its required to shorten the coaxial cables, take care of the red insulation.
Since the E800 620 ESC are coming nicely protected in a case, the mounting is much more safe than it was at former versions and its heat shrinked competitors. Tight zip ties cannot cause damages anymore, the flat surface @ both sides allows a durable fix with tape as well. The shown big Tarot style motor mounts are fitting great.
For the flight tests, a Quad was buildt with TAROT parts. A former Hexa, not very light, not very strong, but sure a good looker, coming with retractable servo landing gear and lots of space. The big motor mounts looked like being made for the 620S ESC. Including battery app. 2400g takeoff weight.
@ 4000g takeoff weight this Quad needs about 480W (app. 22A@6s). Its not really fun to fly, with a shaking 3lbs bottle underneath. Gains need some tuning as well ;-) Starters, don´t do this, might ground your bird.
Plug n fly is working. Flawlessly. No problems at all. The Quad with the DJI Propulsion E800 shows up more agility than with its predecessor. Noise is different, somehow less, somehow deeper.The latter has been already noticeable during the Power Consumption vs. consumption measurements.
The flight tests confirmed (app.) the results of the measurements on the work bench:
Example: DJI Propulsion E800 Kit power requirements @ slow flight / Hover with 2m/s wind. App. 250W (11,3A/22,2V) @ 2400g takeoff weight (Btw. 5-8 W accessories included) The chart illustrates consumption fluctuations (peaks) caused by altitude and position corrections of the NAZA, also turbulences. Wind 2-4m/s, Bigger peaks at the start and at stronger gust impact. Btw., the DJI recommendation of 800g/axis takeoff weight (3200g /Quad, 4800g Hexa) is rather underrated, because several other tests did not reveal any problems with 900g/axis as well.
The tests of this report do not meet scientific requirements. However, all tests were repeated several times with very similar results, which permits the following conclusions:
1. The E800 Tuned Propulsion system is usable for 900g Power Consumption/axis as well, although not advertised. However it has to be pointed out, that exceeding specs (like takeoff weight) might lead to increased wear as well, although one might think that the DJI Propusion Lab is underrating their products.
2. The 20A 620S Sine Wave ESC get along well with the 3510 motors and 1345 rotors @ 6s at advertised operation conditions. Never got hot. Their behavior is excellent, active braking serves perfect stops. No doubt: Their interface and their intelligent Health monitoring will be copied pretty soon, just like the external LED monitor.
3. The manufacturing quality of the E800 motors is visibly excellent. Swiss people couldn´t have done better.
4. Easy handling: The tool free mounting oft the carbon reinforced 1345 rotors with bayonet is simple and comfortable.Usage out of the box without visible flaws (vibration) No more static balancing required, although Pros might want to. (They always will ;-) ) Common users might rather do worse than better.
Pricing / Comment
E800 Quad Kit (4 Motors,4 ESC, 8 Rotors, Tool Box , USB Interface) 319 $
E800 Hexa Kit (6 Motors, 6 ESC, 10 Rotors, Tool Box, USB interface) 469 $
Comment: The price seems high at first sight. Well, new technology. But after some research it turns out to be a good deal,compared to other quality brands, considering what is included, even a great deal. Its the complete package, everything included. However, the price for the 1345 carbon reinforced rotors look like a real bargain, only cheaply made clones can compete with it. Bye bye, Alibaba and Buddycode gambling !
Point of view
The DJI Propulsion Lab did a good job.Customers will find out: Better ist the enemy of good. Although this phrase is used inflationary, it describes very well the relation between the former DJI kits, its competitors and cloners and the new E800 Tuned Propulsion kit . The lab did not just stick to improvements of standard stuff, they designed a complete new system: Introducing sine wave ESC to the world of small and mid size copters, establishing perfect wounded motor coils. Visible perfection, true (R)Evolution. However, DJI sticked to easy building: Like the former program, E800 Tuned Propulsion kit doesn´t require in deep knowledge to build up a great Multi Rotor system.
Users, being used to DJI Plug n Fly setups, looking for a stronger replacement for their overloaded rigs, without getting pretty deep into multi rotor science, won´t get dissapointed with the E800 Tuned Propulsion kit as well. Simple buildt, even better manufacturing quality and new technology doesn´t need to fear the comparison with competitors of its own class.
Buy ! The new middle class for the mass is a first-class replacement for the E600 Tuned Propulsion kit. (Even if this was not the intention) Cannibalization. Vae victis. This product would have deserved Made in Germany as well. (If German companies would serve this market, they don´t). Instead, the proud Created in China announces new standards. For new buildts, newcomers and tuners in favor of plug and fly, the E800 Tuned Propulsion kit is a great choice, for sure.
E800 Propulsion Thread @ RCG
Note: This report just reflects the personal view of the author. Accuracy and completeness are not provided. It is recommended that users stay in tune on the forums and @ DJI site. As always, all pictures of the report and text passages are done by the author, may be copied and also be used in other places for private purposes. The use for E... auctions is not allowed, commercial use by request.
PS: German readers might prefer to read the german version of this review :
E800 review in german language
E310 review in german language (not translated yet)
United States, MO, Springfield
Joined Feb 2014
Really great review! Thanks for doing all the testing and sharing your results. One thing I did notice though, the ESCs don't fit quite as well on the stock Tarot 680pro motor mounts. I believe you are using Arris 16mm motor mounts, my E800 ESCs stick out a little bit on the stock mounts. I wish I got them to look as clean as your set up lol
Joined Feb 2013
Thx, and yes, apologize : Big Tarot style wasn´t an exact description. Unknown source, but in fact, they look exactly like the ARRIS 16mm Clamping Motor Mount Plate/Black for Multicopter AR68B26, available e.g. @ hobby-wing. Thx a lot for the hint.
Joined Feb 2013
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