Month: July 2018

Flyduino KISS 25A 2-5S ESCs (single and 4in1) review

I’ve been flying Flyduino KISS products ever since I bought their first Flight Controller (V1) and 24A Race ESCs back in 2016. Last year I have tried their newer products: 32A ESC and KISS FC V2, so I’ve got good knowledge regarding their flying properties and performance.

This time I will take a look at the latest ESCs from Flyduino:

  • KISS 2-5S 25A single
  • KISS 2-5S 25A 4in1

Testing samples were kindly supplied by Flyduino.

KISS 2-5S 25A

Main features

  • 12 x 26mm and weights 3g
  • 32-Bit-ARM Cortex M4 MCU running at 80 MHz
  • Supporting 2S to 5S LiPo
  • Max continuous current 25A, protective current limiting of max 40A
  • Dshot 100-2400, Oneshot42 and Oneshot125
  • Turtle mode, 3D mode and rotation direction change supported
  • sinHybrid for smoother performance
  • Motors „talking feature”

ESCs come without any wires, so you might need to purchase them separately to avoid surprise. That’s how it always been with KISS ESCs.

25A ESCs are noticeable smaller than previous generations: 24A and 32A which shared the same form factor. New ones are better suitable for compact builds or frames with thing arms.

At closer look

New ESCs are made from a separate PCBs stacked together as it appears on the photos. Soldering pads are small but still comfortable enough to solder. 3 FETs are at the bottom along with current sensor.

 

Compared to 32A ESC?

All features of 32A are incorporated in 25A ones apart from the obvious continuous current value. Form factor change is the biggest difference as far as I can tell.

32A versus 25A (heatshrinked)

Depending on the thickness of wires soldered to ESC the weight reduction between 25A and 32A, considering the size difference was around 1g.

KISS 2-5S 25A 4in1

New 25A 4in1 is essentially four single 25A ESCs fitted on one PCB. Features are the same between single and 4in1 version.

4in1 weights around 12g.

 

At closer look

25A 4in ESC has XT-60 pigtail pads, motors signal pads and socket allowing for connection with KISS FC and also soldering pads to motor signals plus additional VBAT pads.

Motors are numbered as per KISS standards meaning front left is 1 and rest follows clockwise. Numbers are written on the board so it has to be installed in a specific orientation.

I am not aware if it is actually possible to remap the motors on KISS though. M3 holes spacing is 30mm exactly so when this ESC is fitted into the standard frame using 30.5 you might want to use a file to make the holes little bit bigger.

It is the same as with KISS FC where holes never match perfectly because of that 0.5mm difference.

 

Installation

I used my current build based on DemonRC Blaze frame and fitted 4in1 in there. Apart from the mounting holes adjustments there was no issues. I used longer screws to make sure there was enough thread for the soft mounting bobbins and stacked KISS FC V1 on top.

To connect ESC signals with FC I used supplied harness, although it is (unnecessarily) pretty long wires so I had to fly them in-between ESC and FC. VTX power was taken from directly from ESC Lipo pads and FC power from VBAT pads.

Initial power-on revealed that ESC is flashed with the voice firmware, so it „talks” when you power the quad on.

Flight performance tests

KISS 25A single ESC was fitted in the 6” Reverb

Specs:

  • ImpulseRC 6” Reverb
  • ImpulseRC ReverbPDB
  • NorthAero 2207.5 2450kv
  • KISS FC V2
  • KISS 25A ESC
  • TBS Unify
  • TBS Crossfire
  • RunCam Swift V2
  • Turnigy Graphene 1300 4S
  • HQ 5.5x4x3

It is a great cruiser quad and previously it did have KISS 32A esc installed.

I have tested various props but found that HQ 5.5” are the best for smooth footage. New 25A escs fit Reverb arms so much better than previous 32A and nothing was sticking out of the arm.

So how was the flight performance? I won’t going to lie – it was great.

Very smooth since the first second in the air. I didn’t even have to re-adjust pids (which were only increased slightly from stock). Performance was „sharp”, rolls and flips had no bounce backs. I feel that KISS ESC performance has the best out of the box effect compared to any other ESCs and firmwares I’ve tried over the years.

KISS 25A 4in1 ESC was fitted in 5” DemonRC Blaze

Specs:

  • DemonRC Blaze
  • NorthAero 2207.5 2650kv
  • KISS FC V1
  • KISS 25A 4in1 ESC
  • TBS Unify
  • TBS Crossfire
  • RunCam Sparrow Micro V2
  • Turnigy Graphene 1300 4S
  • HQ 5×4.5×3 V1S

I had HelioFC and Blheli32 ESCs installed on the machine prior to this test with KISS. It was never performing as I would hoped for. Ive had all sort of oscillations and weird things going on.
ButterFlight works well on my 7” cruiser but here I simply couldn’t get it to work or I was doing some user errors with filter settings etc. I don’t know, maybe it was my fault.

First flight with 4in1 ESC literarily dropped my jaw to the ground – it flew sooo nice. Very „sharp”, no oscillations, absolutely no trace of vibrations in the footage and butter smooth performance.

Please bear in mind Ive had „old” KISS FC V1 installed because I didn’t have V2 spare for this test. Blaze flew great again and I have made few clips from the flight footage to show it.

Flight Videos

 

 

 

 

 

Conclusion

25A single ESC
Positives:

  • Butter smooth performance
  • All features of 32A ESC but in a smaller form
  • Improved form factor for frames with narrow arms (fits perfect to Reverb)
  • Supports up to 5S
  • ESC telemetry

Negatives:

  • Price. I wish they were a bit cheaper
  • No wires included and they need to be purchases separately (always a case with KISS ESCs)

25A 4in1 ESC
Positives:

  • Butter smooth performance
  • 41in form factor so possible to use with stacked builds
  • Supports up to 5S
  • ESC telemetry

Negatives

  • Price. I wish they were a bit cheaper
  • No wires included and they need to be purchases separately (always a case with KISS ESCs)
  • Included wire harness is a bit too long, I think 5cm would have been enough
  • No plug’n’play solution for powering the KISS FC off the ESC since there is no second socket (similar like on Alien Steele PDB). I had to solder the VBAT to KISS FC directly

New KISS 25A ESCs are a good option for those who want a very smooth flight performance with minimum fuss and configuration required to make it to work.
Smaller form factor is a great bonus, also having 4in1 option is good too.

My biggest complain however is the price still. I understand this is a top quality products but competition isn’t sitting tight and ESC proces dropped over the last few years. If it was a bit cheaper that would be a massive bonus.

Also worth mentioning – new ESCs worked well with new Reverb PDB I was testing but that’s for another article 🙂