Hobby-Wing asked for people to review their Arris 30A ESC and I was fortunate to get 4 of these for my latest project. I'll be building a S500 quad for aerial video. I did not pay for these and what you see here will be my honest opinion. I give credit where credit is due, and will point out things I don't like. Feel free to ask any questions and I'll do my best to answer them. A video is in production as well.
Up first is the packaging. I used to work in product development and know all too well how much time and cost goes into packaging. That translates to a higher final cost. Did you know the packaging for many of the products you use in your home cost more than the actual product inside? Think about that next time you walk up and down the grocery store aisles. I like to see minimal packaging on my stuff. Kudos for them putting their costs into the product and not trash for the bin.
Out of the box there is a lot to like. I'm partial to a nice clean fit and finish. these definitely win in that regard. They shrink wrap is nice and tight, the ESCs are nice and flat, and they have a nice symmetry to them that just looks nice. I have no complaints about how they look.
It is hard not to notice the long wires. They are far longer than I'll need. That means I have lots of extra servo wire and 16AWG wire to use on other projects. Nice!
These don't have motor wires. Rather, they have 3.5mm bullet connectors on the ESC. I usually solder my motors right to the ESC to save weight and increase efficiency. However, since this is a larger (~1.5kg) quad I'm not too concerned with saving every gram. I'll probably go ahead and use the bullets, at least for the initial install and test. I prefer the bullets on the ESC compared to wire with bullets. With ESCs it is better to have short ESC to motor runs. This setup will allow me to plug my motors directly into the ESC with only 4" of wire. that means I can keep the ESCs close to the motor without having to trim any wires. I can also mount the ESC directly under the props. This will help keep the ESC cool. However my motors will run well below 30A so I don't expect heat to be an issue at all. I'm using 4S, 800KV motors, and 9-10" props.
The long wires made it very easy to install these. I trimmed the power leads down to just a couple inches. I left the servo leads as is for now with one exception. The ferric rings were at the end by the servo plug. They should be as close to the ESC asa possible so I moved them there.
The flat profile made it very easy to secure them to the arms of the quad. I really like the bullet connectors on the ESC, makes it easy to put them under the props for cooling (proven to increase power!) without a lot of excess wire bundled up.
These are not true "Opto" ESCs. They do not require power to the signal end, but don't supply power either. These "Optos" are just ones that don't have a BEC, not ones that use an optical coupler to send the signal from FC to motors. It is a minor point as most Optop ESCs are just BEC free, not what Opto really means in the strictest sense.
This is what matters, but also where they start to have minor issues.
-One motor gets much hotter than the others. More below...
-all 4 ESC make a high pitch whining sound. The frequency is about 8,000K. It is very faint, but there. It is probably the way these are tuned. If yo don't listen for it, you won't hear it. (video below)
-3 of the 4 ESCs will calibrate, the one that has the hot motor will not. I just get a single tone at the high end, and again at the low end. This was replaced by the manufacturer and the replacement calibrated just fine and is working out great.
-none of the motors make the SimonK startup arming tones. Not SimonK firmware? **edit** they are using a custom version of the SimonK firmware. They work the same, but the tones are different. The initial 'ba-da-beep.......beeeeeep' sounds more like 'badabeep..beep'. Faster and slurred tones, if that makes sense.
Initially I had some flight issues. I changed props to some more efficient, less power hungry props (APC 10x45MR vs GemFan 10"SF) and that made a huge difference. I tuned the PIDs, mounted the FC better, balanced the motors and eventually got it to be solid, stable, and very responsive.
ESC high pitch sound
Compared to Afro 20A ESC
I have some Afro 20A ESCs that I put on to compare. They operated nearly the same, but didn't feel as smooth on the low end. I even noticed that when I dropped the power to 0 the red light on the ESC would light up (not supposed to do that, that means loss of sync). If I tried to power up when the red light was on, the motor would not do anything. Not good. No such issue with the Arris ESCs. They power up just fine after dropping to 0, and feel a bit smoother at the low end.
Update - February 14
Hobbywing/Arris support has been in touch. They think the ESC that won't calibrate is bad. They are not sure about the whining noise. A replacement (4?) is on the way so I can test some more. If it is just one and it calibrates, thats good. However if that noise is still there, I'm not sure I'd like that. They also said these are SimonK ESCs, but they have modified the firmware. That could explain the tones.
I put my Afro 20A ESCs on the same setup, and it works great. No whining noise and all 4 calibrate. Test flight is essentially the same. However the #4 motor runs cooler (that was the ESC that didn't want to calibrate). However they still run a bit hot on 4S with the 10" slow fly props.
I did hear from the company and they are sending a different ESC to test. Seems they are making changes to the firmware and suspect the one that won't calibrate is bad. I'll update then.
Update March 15
I finally got the time to get the replacement installed and tested. It works great. I prefer these to the Afro ESCs now that I have 4 that will calibrate. The motor was no longer running hot. With the APC props, tuned PIDs, and a vibration free FV mount, it flies really well.
If you are looking for a budget ESC with low weight and good AMP ratings, these are definitely ones to consider. I'll be leaving these on and saving the Afros for another project, or selling them and getting more of the ARRIS ESCs for my next project.