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Old 06-08-2013, 04:51 PM   #1
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Default Can using very light braking burn up a ESC?

I have a top speed car that keeps burning up speed controls. It is of course geared very tall, but has the power, etc, to turn the gear. I keep burning ESC's up on 8s even without putting ANY heat in the thing. My set up is 2 wheel drive and because of this I have to turn the breaks WAY down.....like 20%, or the back tires slide. Could the combination of tall gearing and very slight braking be contributing to this problem?
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Old 06-08-2013, 09:13 PM   #2
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What speed controller are you using? Is it rated for 8S?

By the sounds of it, with the limited information provided, you are running too much voltage through the speed controller.

If the speed controller can handle 8s, then I would check all your solder joints, especially on the motor end bell. You may have to take off the end bell where the solder tabs are and check that there isn't a short between the tabs on the motor. Sometimes if too much solder is used when soldering the wires to the motor, the extra solder will form a bridge between tabs or to the motor can.

Also check the solder joints on the speed controller. Make sure there are no short circuits.

If you are using a castle system, then once again, check all connectors and inspect the motor can.

Hopefully this helps, or gives you a starting point to solve the issue.
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Old 06-08-2013, 09:33 PM   #3
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more info ; motor . speedo used FDR ... you might just be running too tall . even if it does have power to pull the gearing ... what car/truck are you running ...
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Old 06-09-2013, 06:54 PM   #4
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I'm currently using the Trackstar 1/5 scale ESC.
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Old 06-09-2013, 08:22 PM   #5
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Originally Posted by TheStnchOfSpeed View Post
I'm currently using the Trackstar 1/5 scale ESC.
I dont think its a ESC problem .. might check out the drive train of your car ,, sound llike you have something binding maybe bearings .. if there are bad ones they show up when there is some heat build up in them and when you check them cold they seem ok .. using light breaking i doubt will cause the problem your having .
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Old 06-10-2013, 01:58 PM   #6
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Bearings etc are all in good shape. As a matter of fact most of them are new.
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Old 06-10-2013, 02:11 PM   #7
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I know nothing about that speedo but according to this:

http://www.hobbyking.com/hobbyking/s...s_car_esc.html

It's only rated for up to 6s. I would say that is the problem.
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Old 06-10-2013, 02:51 PM   #8
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Quote:
Originally Posted by wingracer View Post
I know nothing about that speedo but according to this:



It's only rated for up to 6s. I would say that is the problem.
That's the wrong one. As I said, I'm using the 1/5 scale one. It's rated for 8s.
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Old 06-10-2013, 02:54 PM   #9
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Does anybody actually know what the capacitors are actually doing? I know what capacitors do but I wonder what they are used for in a speedo. There has to be a reason I am cooking the leads off of them.
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Old 06-10-2013, 02:54 PM   #10
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Quote:
Originally Posted by wingracer View Post
I know nothing about that speedo but according to this:

http://www.hobbyking.com/hobbyking/s...s_car_esc.html

It's only rated for up to 6s. I would say that is the problem.
that's the 1/8th scale ESC. He said 1/5 scale, so I would assume this one.
http://www.hobbyking.com/hobbyking/s...o_Car_ESC.html

Speed runs don't do it for me, but if I was to build something for that purpose, I'd probably use an ESC rated for far more than I would plan to give it. Like something capable of doing 12s. Maybe an aircraft ESC.
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Old 06-10-2013, 04:29 PM   #11
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The capacitors keep the voltage levels down. With the high frequency switching, you could possibly see up to triple your actual voltage at the input of the speed control. Now to figure out if the issue is caused by the caps coming unsoldered or if the issue is the caps coming unsoldered. For your use, I'd suggest lead free solder as it has a higher melting point and I'm sure you are building a lot of heat. You could add extra caps as well.
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Old 06-10-2013, 04:29 PM   #12
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It is probably your gearing, that is what usually, other than shorts, kills esc's

too small pinion esc hot
too big pinion motor hot

what are some of your motor and esc temps after a run?
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Old 06-10-2013, 05:06 PM   #13
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Quote:
Originally Posted by JayL View Post
It is probably your gearing, that is what usually, other than shorts, kills esc's

too small pinion esc hot
too big pinion motor hot

what are some of your motor and esc temps after a run?
The most recent time this happened, it happened before I even made a run. ESC and motor were DEAD COLD. No temp whatsoever.
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Old 06-10-2013, 05:09 PM   #14
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Quote:
Originally Posted by linkless View Post
The capacitors keep the voltage levels down. With the high frequency switching, you could possibly see up to triple your actual voltage at the input of the speed control. Now to figure out if the issue is caused by the caps coming unsoldered or if the issue is the caps coming unsoldered. For your use, I'd suggest lead free solder as it has a higher melting point and I'm sure you are building a lot of heat. You could add extra caps as well.
The caps aren't coming unsoldered. The leads are literally melting in two. The cap itself looks perfect other than melted leads.
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Old 06-10-2013, 05:45 PM   #15
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Quote:
Originally Posted by linkless View Post
The capacitors keep the voltage levels down. With the high frequency switching, you could possibly see up to triple your actual voltage at the input of the speed control. Now to figure out if the issue is caused by the caps coming unsoldered or if the issue is the caps coming unsoldered. For your use, I'd suggest lead free solder as it has a higher melting point and I'm sure you are building a lot of heat. You could add extra caps as well.
Function of capacitor. 1) Filter out AC Noise in AC circuits. 2) Acts like battery with DC circuits. RC's DC circuits act like a battery, with NiMd or lipo's jumping or fluctuating in voltage. It keeps the 6v it needs to operate servos and ESC.
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