Mamba esc w4s & bec overheating..help?
 

Guys, i need some help...bad.....

I've got a mamba esc with the cc bec in my truck, and i've smoked 2 other escs this month. I'm runnning it in a Rustler vxl with a thunderpower 25c 4s 5000mah lipo and a neu 30c 4100 mah lipo with the vxl motor. I'm at a loss right now as to why it's happening.

I hooked it up just like they illustrated on the CC site except for one thing...

the bec wires that go to the esc that are supposed to be soldered to the connector that plug into the battery were soldered on each wire near the base of the esc....like this:

http://i247.photobucket.com/albums/g...t/HPIM3978.jpg

could this be the source of the problem?
I also eliminated the on-off switch...but i see alot of people do that.
is running the fan too much on the esc?
I bought the mamba specifically so i could run the 4s.....do i need any capacitors or anything?....

any help would be greatly appreciated.

Please could you take a pic of the rx - you removed the red wire on the MM rx lead I take it - A novak HV 2700uf cap or same could help...

try gearing down ?

J.

yes, i removed the esc bec wire...sorry, i forgot to mention that....also, the RX is a traxxax e-maxx 3 ch but have used a 2ch futaba too...I have the servo plugged into ch 1, the esc plugged into ch 2 and the fan and the bec plugged into ch 3 with a y harness.

here's the pic...sorry it's so hard to see...i have a poor camera.

http://i247.photobucket.com/albums/g...t/HPIM3979.jpg

where would i attach the capacitor?

The MM ESC should have no problem handling that setup.

Be SURE that you lift the red wire from the ESC to the Receiver. If you didn't, this is what's causing your problem. You can NOT have the ESC AND the BEC both trying to power the Receiver/Servo's.

IF you did lift the red ESC wire going to the Receiver, I would suspect there is something wrong with the motor.

Gearing? 4S is alot for the VXL Motor but you should be able to run it on 4S, as long as you keep temps in mind during long runs. Does it cog?

Have you updated the firmware in your ESC?

Your soldering job looks fine. :yes:

I'm using the MM/CC BEC in an E maxx setup. It performs GREAT. Power comes from 4S 5000mah 20C Lipos. I do have a Novak Cap added and a fan on the MM.

It will out accelerate AND outrun the T maxx on top end. :yes:

Can you post a picture of where your wires plug into the receiver?

yes, i updated the firmware the day i got it. :)

am i missing something?

i read in another thread about programming the bec through the castle link...but how do you do that? there is no usb port on the bec....

man...i'm lost.

Oh ok. Take a look at this page:

http://www.castlecreations.com/produ...stle_link.html

Do you have the little thingie pictured in the upper right hand corner?

There is Castle Link software, then there is a Castle Link Module.

The USB cord plugs into the module and the module plugs into the CC BEC.

How hot does your motor run? Does it cog?

http://www.castlecreations.com/produ...stle_link.html

You use this to program through the receiver lead of the bec.

Edit: sikeston34m beat me to it.

got it..... thanks!! so will changing the voltage make the bec make the esc run cooler? and what should i have it set at?

Using a BEC will make the ESC run cooler, but the esc doesn't care what voltage the bec is set at. so the answer is No.

I have mine set at 6.0 volts.

If you're looking for ways to make your ESC run cooler.

Go back over your setup in the ESC. Turn the timing down some, and how about some punch control?

Just remember, you are powering a motor on 4S, that was really meant for 3S. This is going to make it draw ALOT of amps.

thanks...i think i might be geared too high as i'm hitting about 1850 watts when i should be at around 1400...i might need to also set the factory defaults back instead of having zero punch control and the timing turned all the way up...etc...i had everything set for the absolutest worst place to help cooling. :gasp::surprised:

Also, would you recommend the HV capacitor? what exactly does it do?

What is the fan everyone is running on the MM and how do u attach it?

this one...

http://www3.towerhobbies.com/cgi-bin...&I=LXKKN0&P=ML

i screw it directly into the heatsink..it's a perfect fit.

The Added Capacitor helps to smooth things out in the powerline.

There are several added advantages that it gives your setup. Without going into a lot of technical detail, it can help your ESC run 15 degrees or more cooler.

If you want more information on what it does, there are numerous threads here that discuss this topic. Be warned, it gets deep! LOL

Sounds like you might indeed be over geared. Try setting the timing on the lowest setting and give it some punch control. (50% or so). This will help tame those huge current spikes on startup.

thanks! I just re-programmed it and went down 10t in the pinion and up 10t in the spur.....

now.... got anything on getting the rain to stop? :lol:

Wow, that's a whole lot of gearing change. Make sure to keep an eye on the motor temps. Unless you were severely overgeared, you might have it geared to low now, lol.

J.

I was geared 66 spur/40t pinion...i went to 76/30.... :gasp:

I looked up some info on the capacitors, and it said to solder them between the 2 power wires....there was a place for the pic, but it had been long since removed.

do those novak capacitors get soldered between the 2 wires from the esc that plug into the battery?

can i solder them to the wire and not the board?

solder them parallel (along with) the batt wires that go to the esc. The capacitor acts like a super fast charge/discharge battery, just put it as close to the esc as you can. Yes, the standard is to solder them to the esc wires, not the board.

thanks....i heard of someone in another forum using 3 of the capacitors...is there any advantage to this or will one be enough?

one is apearently enough, however the more the better if you have room/weight to spare ect... when you get multiple caps on there you do tend to wear the connectors fast (arc's). I did a 4 pack on mine, grouped them togeather and put a deans on the input and output. I used them on my XXXT but I don't on my 1/10th 4wd buggy...

you may be thinking of the upgrade to the existing 3 caps too. sorry, just clicked :)

thanks...much appreciated...

as to the 3 upgrade caps, i think i've seen that before somewhere.....i'm terrified to try to go solder anything to the boards...i think i'll try the novaks between the 2 power wires.

76/30 sounds more like it. 66/40 is crazy!

apparently the other 2 mambas thought so too. :lol:

I have VXL Rustler that I have a MM, 4 cell 5000 lipo, and 54/15 gearing, running the CC BEC and the Battery and ESC barely gets warm, and the Feigao 9L gets between warm and hot, and I dont run a fan or extra caps...I would shoot for about a 3.5-1 gear ratio and with the 4 cell and stock VXL motor your getting over 50,000 rpms I would say that is beyond its max

Well, i gotta hand it to you guys...when you're right... you're right... :yes::party:

I just came in from some testing, and temps never got above 117 degrees....and it's almost 75 outside right now....i lowered the timing and changed the gearing and gave it some punch control.

That was geared 76/30=2.53...i think i could go even a few teeth higher and it be fine....i might mess with the throttle curve too although i kinda like where it's at right now.

Crazy how sensitive this esc is compared to the vxl....with the vxl i could run 19 - 40t on the pinion and 7-10t difference on the spur and there be maybe 30 degree difference in temps.


With the mamba, 10 teeth on the pinion, 10 on the spur, and timing on high means thermal....just sucks that i had to go through 2 esc's before i got my head outta ...wait...huh? LOL ......and just asked for some help. CASTLE RULES!!!!

Again, thanks guys. :party: