ZTW have been well known for producing only the highest quality Electronics for quads for well over a year now, and the new Flash 30A are no exception.
- Supports high kV motor and BLHeli REV 16.0
- Autodetect Oneshot125, Oneshot42 and Multishot
- MCU- EFM8BB21F16 and hardware PWM make smooth throttle responses.
- Note: There is no max cell count but our research of the VReg suggests a maximum of 6S.
Initial Impressions and Installation:
The ESCs came like pretty much every other ESC we have ever seen, in a grey antistatic bag. The ESC was a little larger than we would like. Here are the dimensions we measured.
The PCB does seem overly thin as well, at only 1.05mm thick, especially as we are carrying serious current nowadays, sometimes in excess of 30a. Apart from that the Signal cable did seem very long, and you may want to cut it own for miniquad use. The wires were all silicon insulated as we have come to expect from most ESCs.
There’s not much to say about soldering up the ESCs either, although we did cut down the cable for use on our SCX and also used a grounded signal wire.
We used the BLHeli Passthrough feature of cleanflight to setup our ESCs on BLHeli 16.1. Once setting we did change was startup power to 0.125, this was simply a safety net to ensure we did not have any death roll issues. A very small minority of users are reporting issues with BLHeli_S deal roll issues, and those who are are generally using the Aikon SEMF. We did not experience any issues with the Flash 30A throughout our testing period and we have not been able to find anyone who has had any issues with these specific ESCs.
The Flash 30A are designed to operate on BLHeli_S firmware, and thus it uses a Busybee2 (EFM8BB21F16). This MCU is faster than we have previously seen in standard BLHeli_S ESCs . What is the advantage of this faster processor you might say? Well it enables the ESC to use hardware PWM, whilst we are not computer programmers, from what we understand it is far better than the software PWM that most previous ESCs are using. This also means that the ‘refresh rate’ between the gate drivers and MCU is double what it was before. The ‘Busybee2’ MCU is a step above the ‘Busybee1’ we have seen in other BLHeli_S ESCs, therefore it has 2048 steps of throttle resolution. Although no one is quite sure whether the ESC/FC can actually use this greater resolution.
As you can see from MiniQuadTestBench’s Graph, the ZTW Flash 30A perform right in the middle of the pack, they don’t quite beat out the Aikon’s or EMAX BLheli_S. But they do perform very similarly to DYS’s XS30A.
Click here for a full spread sheet of results.
However static thrust tests are only half the story so here is our view on how they performed in the air.
We were flying a fast racing quad, the SCX 200, with a 11:1 thrust to weight ratio so we could really push the ESCs to their limits are we were not disappointed. BLHeli_s makes a huge difference to performance, especially near the bottom throttle when recovering from maneuvers and requiring the motors to spin up smoothly and rapidly. The change in performance v XM30A strikes us almost as bold as when we first used KISS ESCs, coming from the days of flashing 12A HK Blue ESCs with SimonK, it really was this outstanding.
The ZTW Flash 30A are some excellent BLHeli_S ESCs, they avoid the issues of the early adopters such as the Aikon SEMF 30A and the (now recalled) Emax Lightning_S 35A. But they still maintain solid thrust numbers and the crisp throttle response. In addition the BusyBee2 MCU acts as a good future proofing net when later generations of BLHeli_S come out. But the drawback has to be their large size and very thin PDB, which is annoying if you are building very tightly. Nevertheless it is still a steller performance from a top quality manufacturer we have come to expect no less from and therefore it is our favourite BLHeli_S ESC to date.