Tres

iTrader: (14)

Short circuit protection would be hard to do and cause a loss of ESC performance I think.

As the resistance of the motor is so low to begin with.

Tekin Prez

This is an extremely fast event thousands of times per second.. unless you are full on. It is a dead short across a very impressive battery built to deliver high current quickly.... but not this quickly. The problem is the type of load, resistive versus inductive.

Both hoods is the worst, but either hood can create some interesting circuits thru the conductive chassis to other points.

Tekin Prez

Tekin Prez

Found another today that burned up a Rebel esc. Sure enough the motor in question had a shorted endbell to both brushhoods.... and turns out had burned up a speedo before this and why they bought the Tekin Rebel to begin with.

If we do not warranty these failures, which we should not, this may be good for sales....but bad for ave Joe...

Tekin Prez

Tres

iTrader: (14)

Hmmmm.....

I wonder why not much response from the motor guys???

killswitch

iTrader: (2)

I was thinking the same thing. Anyone?...Anyone?...Anyone?...

DustinR

iTrader: (10)

I have had like 12+ Orion V2 motors. And of those12, 2 endbells have shorted. I am running the LRP QC1 and although the endbells were toast the ESC has always been fine. Just shairing,

"ULTIMATEPOWER"

the v2 series are really bad about this situation, due to the endbell being solid aluminum they have to glue the brush hoods in, thus them being round doesnt help the subject once they get hot over several usages... also the capboard is on the inside which doesnt help things at all, if top would replace/change the brush dampners on the inside of the bell i think it would help alot of the problems.

The Epic shock series has an aluminum bell as well, but we havent had any problems with there bells, epic uses alot higher quality glue and cap board, plus the brushes are parallel with one another not causing them to bounce around as bad.

Just my .2 cents, and from experience with these motors.

Stefan Millay

iTrader: (1)

If you run the V2 motors I reccomend removing the endbell and cleaning it every 3 runs. I had a V2 motor showing a short from both hoods to the can. I cleaned the motor and it was open. The brush dust was causing a short.

PitCrew

Uh...
THe parallel brushes are more condusive to brush bounce than the V2 endbells with their angled brushes. Thats what the big deal is with those and why the comm last so much longer. The axial forces applied to the brushes from the comm's rotation is not able to push the brush away, therefore there is less brush bounce on the comm, and the comm lasts way longer because there is less sparking and mechanical wear.

And, I have heard of major problems with the epic endbells, namely the Shock motor. From a large OEM company, they had to send back a BUNCH of motors because they were shorted when they were brand new. Something about the brush tubes scratching the anodizing off when they are assembled...

Just note that the "glue" in these cases is NOT what insulates the brush tubes from the solid aluminum endbells. It is the anodizing. And, if the anodizing isn't done correctly, or it is not thick enough, it can be scratched and cause a short. If anodizing is done properly, it is VERY difficult to scratch, and the anodization is VERY hard, something like 60 HrC...

asw7576

Place automotive fuse 30A between ESC & MOTOR ( positive / red ) and battery terminal ( positive / red ). Direct soldering to fuse's legs.

ESC positive terminal ---| -------> 30A fuse ------> Battery Positive
MOT positive terminal ---|


Good thing about it : If you mistakeny short the battery positive to negative and vice versa, the fuse will blown.... saving it from mosfet burn. Ditto with failed motor scenario.

Bad thing about it : your car look weird.

Stefan Millay

iTrader: (1)

Thats interesting, would a 30 amp fuse be enough though? With these solid endbell motors a short can happen at any time. A crash or someone rams you from behind (offroad).

Tekin Prez

I do not expect a fuse would offer any protection for an endbell short, but would protect against a dead short somewhere in the wiring. Most fuses are rated generally with a amp rating, but require a much higher current for some period of time to blow quickly. The endbell shorts do not neccessarily pass more power than a good motor.... they just pass it different due to the lack of inductance and allow for almost instantaneous changes in current.... and that is a bad thing if you are a FET...

Tekin Prez

FBJ's RDX

This is kinda off topic...What would be the best way to check for if your armature has shorted out? Thanks

DA_cookie_monst

iTrader: (1)

This is guess work but.... each stack should have the same amount of windings and amount of wire on it, so in theory, each stack should be pretty close in resistance. So you could measure the resistance of each stack (using a multimeter on each segment of the comm, working around), two stacks would be similar/same and one stack would have a far diferent reading.

Tekin Prez

Pretty difficult to measure with a digital voltage meter... we are talking about milli ohms. Also a short does not neccessarily change the resistance, but can eliminate winds.. which is torque... if it is between windings or short to other places and cause various issues. You may see a comm plate that is different than others due to current surges in that winding or lack of

As always HEAT is king in electronics. Bad motors get hot and just do not run good.typically lack "clear the tripple punch" and run time.

Tekin Prez