Quark 125B / Sky Technologies

[BrianG]

Sky will have to use whole new FETs for any higher voltage ESC since the ones they are using are only rated for 30v. The datasheet for the 125B's FETs is attached.

I'm not sure the thermal problems are because of a poor heatsink. Look at the MM; it's almost the same current rating and the HS is much smaller. The resistance of the MM is claimed to be 0.0003 ohms, while the 125B is claimed to be 0.0036 ohms. That might be part of why the MM runs cooler.

Sky can do a few things to make it cooler without using a large HS: Run FETs with lower RDSon, use more FETs to lower the overall RDSon, and make the FETs switch better (reduced slope, not increase in speed).

I really don't think they will allow internal epoxy being used because it won't allow them to take it apart to fix it.

Edit: Forgot to attach the datasheet. :dft009:

[jhautz]

Hey NewE... I did discuss the heat issues and the 6s issues with Frank over at S&T in Cali. What I was basically told is that they knew about those problems but had no plans for chages to the current ESC line. The way it was told to me was that the 125B was originally inteneded to be the ultimate 1/10 scale ESC, but it wasnt really intended for MT and 1/8 applications when it was originally designed. They themselves have done some experimentation with the 125 in Emaxx and 1/8 buggies and have had about the same sucess we all have demonstrated.

When I asked if there was a revised version of the 125 planned to address the heat an 6s issue I was told that there would be no revisions, but that they (S&T Korea) have high on the project list a new ESC that is more traditionally designed with the heat sink on the top that would be targeting the large scale brushless stuff like the Monster Trucks and 1/8 Buggys and Truggys.

Other than that I dont really have any additional information. I asked more questions, but at that time(last fall sometime) it had not even been started, so he didnt really have any more info than that. There was no mention from him as far as max voltage or anything else. I dont want to start any rumors of what it migh be cuz I dont even think they know what it will be. Who knows when/if it will arrive, but if they are gonna play in the same arena as the MMM when it comes out they better do something. Not sure what the MMM will be like, but knowing CC Im sure it will have an impressive set of specs.

EDIT: I just hope the price tag on this new ESC doesnt go up from the 125B cost. Right now its already an expensive controller. I cant imagine many will buy it if the cost goes up from there.

[Serum]

Maybe it sounds a little off, but it think it's time for the MMM to show up. I think it will shatter the quarks. No matter what Quark is going to produce, the MMM wil be my 'next generation' controller. it will force them (or any BL controller producer) to produce BL controllers for a low price.

the programming on the quark is a true PITA..

[neweuser]

Originally Posted by Serum

the programming on the quark is a true PITA..

Thanks for the info Jhautz. From my understanding as well, they really do not repair esc's but "replace" them. And I agree, the MMM will be top of the line. otherwise, I may just go back to BK stuff that I started with. I can keep them cool, and they are dependable for the most part. With my exp on my radio, I have also managed to make the BK's a tad more responsive as well a long with the programming thru the puter.

And serum, I never thought I would hear you say that! I agree, the Quark is a PITA to program! You first told me it was easy when I was having issues! LOL...in comparison to the MM, it definately is a PITA....but, once you get it, you got it. I have not had to re program my Quark since I have set it...I'll say that!

Once winter passes, I really want to test my Neu on the Quark to see the differnce is between the 10xl and the Neu as far as temps on the esc. I'm guessing quite a bit due to efficiency, I also dropped from 5s to 4s, so I'm hoping all this will make the difference.