Hey Sike,

Thanks for the suggestion. I emailed the seller and will see what he says. Not a huge deal for me since I knew from the start it was a questionable purchase.

I am, however, very curious to know what went wrong. Here are some pics, but until I hear from the seller, I can't take any pics of the brainboard w/o the heat shrink. I know you can't see much with the heat shrink in place, but it may give the seller a reason to void my claim. If he says "no", then maybe I can send it to you to take a look at. I'll send you a pm with more details if I get shot down by the seller.

- Rich

I haven't messed with mine yet. Kinda busy here at work now. Motherboards are getting reworked, so my ESC got to wait now. Modellfun did say that they would replace mine if I shipped it back to them.

I understand.

Is there any signs of melting heat shrink on the mount? (velcro side?)

It looks like some blown FET's from what I can tell. The power board went poof. Hmmmm...........

I like how these are laid out. The power board is nicely arranged. I was hoping these would kick butt. I've been watching them for awhile.

Thanks for the Pm, in advance. I appreciate that.

I would like to know what went wrong too.

Are those Caps Bulging? :oh:

Yeah, one is big time. I think it ruptured b/c there is some sticky liquid on top of the cap.

I still think this could be a VERY good ESC with some mods. :yes:

It's pretty obvious it is lacking in the cap department. This means the powerboard is catching some pretty big spikes. Especially at the instant the caps fail. :surprised:

I have some higher voltage FET's that I believe are the same size as the ones used on that power board. I'm very curious about this.

Is the bottom melted? Not the heat sink side.......the other side.

No, the bottom is fine and the motor lead side is fine. The only damage I can see with the heat shrink in place is the caps and the side of the powerboard where the heat shrink melted.

i have one for sale with the programer, if some one is interested ??? PM for price

Edited by Serum; prices only discussed by PM or email.

sorry, i didnt know

Ok, I just heard back from Modellfun and they offered to replace my esc. Good news. It shows that they are not just a chop shop. However, in the interest of science, I've sold off my esc to Sikeston34m so he can run some experiments on them.

I received the ESC in the mail today. Thanks. :yes:

I cut the shrink off and took a look.

The power board looks ok. I haven't removed the heat sink, but I can see the edge of each FET and they look fine. Usually when a FET goes, it makes a mess.

The caps are bulging and the insulation on their leads is almost fried off. There are 2 of them and they are rated at 35v @220uf. These are VERY small IMO. It would do much better with larger ones or at least multiples of these. About 5 of them at least instead of 2.

The Brain board has problems. It smells burnt. I can see one small component that is fried. I will spend some time carefully unsoldering and lifting the power board to discover exactly what the problem is.

Here's what I think. The BEC circuit on the power board is gone. This has dropped power to the brain board. Thus making it "brain dead". LOL

To test this theory, I was hoping it would become functional being powered with an external BEC. No Dice. So the internal BEC isn't even putting out enough power for the Brain to function.

With external BEC power, the brain board heats up quickly. It definately has a BEC problem.

Were you using an External BEC with this on 5S? Or just the built in one?

On mine I used a Ebec, when it blew. When the brain was taken out there was a mess on some of the chips. It looked burn at first, but it was just nasty flux.

Those caps are small huh. The heatsink just pops right off, as it's just sitting on a thermal pad.

Yes, these caps are small and overloaded IMO. It's pretty obvious when the power lead insulation melts like this. They were running very hot.

So what blew on yours?

I was running an external bec, which also fried at the same time the esc did. I think it may have been partially my mistake since I forgot to disable the internal bec. whoops.

Hmmmm............

What voltage was your external BEC set at?

hey, do you guys think this esc could work with a large outrunner in my direct drive tmaxx?

6v. its was the koolflight ubec from here.

Ouch!

With the External at 6v and the internal at 5v. This is probably what took them both out.

The external probably went first, then the shearing heat of a 5S battery set in on the internal BEC.

si there a way to disable the internal bec?

Yes. All you have to do is lift the center "red" wire from the ESC to receiver plug.

just cut it out? and can someone answer my question, will this esc work for my t-maxx on 6s? (large outrunner)

You can either cut it, OR just pull it from the connector and tape it back.

Taping it back makes this easily reversible.

6S with this ESC is probably pushing it. Direct Drive with an outrunner? Hmmmmm............... It might work.

well for $85 and free replacement i dont see why not!

any news on this?

Hey sike... this is off topic, but I just saw a little show on your hometown. Looks nice! They showed the restaurant where the waiters throw dinner rolls at you... looked like fun and good food. It makes me hungry for some chicken fried steak. mmm.....

No new yet. I need to lift that brain board and get a better look. I have a feeling the brain board might be bad though.

Aaaah, you must be talking about Lamberts. We have ate there several times. There's a guy that comes around pushing a cart full of fresh out of the oven rolls. He yells "Hot Rolls!!!!!!!", you hold your hand up and he throws one across the room at ya. LOL

They have some great food there. It's nicely laid out too.

Sike,

Are you going to post pics of the brainboard here?

OK, I got the Brain Board lifted.

Here's a picture.

OK class! Quiet down! Can anyone guess what's wrong with this picture?

That's any easy one huh? OK, is there an advanced student in here that can tell me why this happened? :lol:
http://i160.photobucket.com/albums/t...m/DSC06835.jpg

Does anyone have a Brain Board that would make a good transplant?

It's kinda hard to tell what exactly those are that blew, but to me they look like diodes (on the right). On the top left something else looks blown, but I don't know what it is.

Those two components are connected in series to the center (red) receiver wire.

Internal BEC?

Do I win anything?

Ding! Ding!

Now let me tell you what you didn't win! LOL :rofl:

The big square thingie in the top right with the legs. Well that is a linear regulator. Those things you hear about that reduce the pack voltage to 5v? Well that's the heart of it.

The two burnt thingies, I believe to be Diodes. I'm not 100% sure on that though. (Griffin, can you help me out here?)

One thing that was very puzzling about this is the fact that we have continuity between the red receiver (power) wire and the Black Negative.

I spotted a melted spot in the receiver wire. Very flat and I was thinking this was the source of the whole problem. I removed the wire. Problem is still there.

I removed the two burnt thingies and the continuity is gone. Even though continuity is now gone, I still don't have infinity.

I'm still getting .288 kohms between the Linear regulator and the red wire.

I believe the regulator chip is fried too, even though it doesn't show as much damage externally.

Can I remove the regulator altogether and run this ESC with the Opto Mod?

Well, from my extremly limited knowledge, the brain has to have some sort of regulated voltage. An opto isolated esc does not have the current ability of a bec built it, but must have some sort of regulated supply for the brain. Time for the smart people to tell you what to do.

How about I eliminate the onboard bec, then just feed the Brain "through" the red wire from the external bec?

Sounds like I would have to keep the external BEC set at 5 volts though.

Hmmmmm..........

Sounds like it could work. However I would consult Griffin first to see what he thinks!

I'm not 100% sure, but I think you can. Here is a picure of an OPTO Hacker controller (http://www.rc-monster.com/forum/atta...2&d=1202243485) and you can see 3 silver spot where usually those components would be. Probably tomorrow I will send Artur my Hacker and the other ESC to see if he can swap MCUs. Sikeston, can you post the number on the driver and what that symbol is? Also, what is the part number on the MCU? It looks very much like a Silicon Labs.

This is some really tiny stuff. This Camera can see better than I can. LOL

I hope this helps.

http://i160.photobucket.com/albums/t...m/DSC06839.jpg

Nice. Thank you.

In the voice of Steve Urkel

"dddiiiidddd I doooo that...?"


oops. so it was the bec. umm... my fault. :oops: