Cooling Fan Causing Brown Outs??
 

Hey y'all,

I've got a drifter that is running a brushless (sensorless) Castle 4600 kv motor & Sidewinder combo on 3s. The other day I added a Castle cooling fan to the motor. It gets power straight from the 3rd channel of the receiver. Everything was going great, but after about 5-10 minutes of consistent use it seems to shut down entirely. The car becomes 100% unresponsive and the steering locks to one direction. Powering it off/on brings it back to normal use.

I suspected the old steering servo so I replaced it with a newer one. Last night I was testing it out and the same problem happened. So I decided to unplug the cooling fan and try again. I was able to run the car w/o any more problems the rest of the night.

Nothing is running excessively hot so what could cause this kind of shutdown? :cry:

When you repower the unit (after it stops) how long does it run then before shutting down?
It's possible that if it's a short run time after cycling the power that you are hitting the LVC on the ESC.

the sidewinder's internal bec is very weak on 3s, so with the servo being turned with the fan going could be easily overloading the bec

It'll run another 5-10 minutes or so, sometimes less. And it'll keep doing that over and over. The LVC is set to "Auto" which IIRC is 3.1 v/cell. And the battery still has plenty juice left.

True, but after it browns out from the amp draw, shouldn't it come back? Mine doesn't. It needs to be powered down, then back up. :cry:

You are blacking out the system, and the ESC doesn't like it. It has to be rebooted. Install a BEC or get rid of the fan.

Thanks, John. And I guess you're right to use the term "black out" instead of "brown out" in this case! I never would've thought the servo on a drifter coupled with that teensy fan would draw more current than a Sidewinder could provide, but I guess you learn something new everyday, right?

Alternatively it could be the battery dropping voltage under load causing it, but from the sounds of it the internal BEC is just overheating from the fan. 1a for 10 minutes is rough considering your setup.

Its the internal BEC on the sidewinders. I have a sidewinder on my slash and it did the exact same thing, installed a ccbec10amp and everything is happy now. The bec does not like 3s it overheats trying to convert the input voltage to the set output voltage. (to put it simply)

I guess all that makes sense. Thanks, guys. I guess I'll pick up a BEC for the drifter now! That statement just cracks me up for some reason. :ror:

I was unable to get a BEC installed so I ran the car w/o the fan plugged in and it ended up shutting down on me again. I noticed this time the Sidewinder ESC was blinking red. Powered down, powered up and it was fine again.....just like it's been doing. So maybe the fan isn't the culprit afterall. :cry:

Do you have a different battery to try? That sounds like it may be the LVC tripping early.

I've tried with two batteries of the same make/type and they were fully charged in some cases.....and 5000 mah to boot! LVC is currently set to 3.1 v/cell.

I just checked Castle's site and they don't appear to have any docs online any longer for the Sidewinder, but for the Mamba Max 1/10th they say the flashing red means it's thermaling. http://www.castlecreations.com/suppo...mamba_max.html

So if that's the case I may need to look into a fan for the ESC, too. I'd better get that BEC installed, huh?? :ror:

I start corrected. I see that a flashing yellow/red is an overtemp. However, I thought I saw yellow, but because I was looking at the flashing LEDs through the window of the lexan body I figured it was just some light bleedover or something playing tricks on me. In hindsight, it likely WAS flashing red and yellow indicating an overtemp condition. I'll need to test it again, but I'm pretty sure this is the problem now. I'll get a BEC, some fans, and do some more testing.

When I switched my yokomo drifter over to lipo she started overheating . Novak SS plus esc with SS5800 sensored motor running on 2 cells .
What I had to do was go down two teeth on the pinion gear to make it happy .
I didn't loose much on torque or speed . Drift cars just don't get enough airflow . Maybe this will help ?

Good point. I do recall using a larger pinion gear simply because a smaller gear couldn't get close enough to the spur. I now have a larger spur gear so I'll slap it in and gear it down. Lord knows it has excessive power already! Gearing it down can only have good results. Thanks! "thumbsup"