WTF HAPPENED

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No worries. I'm still learning so critical feedback actually benefits me. Thanks.
The reverse throttle part I've done with the Radiolink several times with no issues before. But it only takes that ONE time to hardwire it into my head that it's a no-no. Thanks for telling me that and rest assured it will be the last time I do that on ground powered up. That explains one thing at least.
1. No, in fact I triple checked both ESC and radio fail safes for proper setup. After you mentioned it, I just checked again. All good.
2. The main visible things were set at zero prior to calibration. I actually reset the profile just before(thanks Alan!)
3. This is the second time brownout has been mentioned. Still learning and would appreciate more info on it or a link as searching it gives many mentions with little detail. As for servo, it's a 35kg JX Ecoboost HV. You are right about that though. Seems fine when on stand and poops the bed on ground.
LuckySSR JX Servo Ecoboost CLS6336HV 180° 35KG Large Torque Servo CNC Coreless Digital Servo for RC Crawler Car Helicopter Robot Boat https://www.amazon.ca/dp/B0872CRKJD/ref=cm_sw_r_apan_glt_i_AJH3VT3B23VQ12G1Z348?_encoding=UTF8&psc=1
What you said gels with what jkflow said after the fire. Actually brings me peace of mind because I like the RadioLink, I'm used to it now. Knowing both incidents can be blamed on me helps. I can see how I got lax and careless and based on what you both said, I failed to followed proper procedures.
Why is this good? Because that's something I can fix and change that won't cost anything but rather instill safer habits.
 
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Brown out.
Short version: When the BEC goes below the rated receiver voltage, bad stuff happens.
Your BEC circuit in the ESC can only provide a certain amount of current at the rated voltage. For a Max6 it's 6V/7.4V and a cont. /peak current of 6A/25A.
The 25A peak is misleading, but I'll answer below. The magic formula here is that electrical power will stay constant. 6V*6A = 36W or 7.4*6A = 44W

Everything you plug into the receiver draws current. I could not find any info on your Ecoboost, but these are typically in the 4-5A range, they draw more current at higher BEC voltage (higher torque). That is worst case.
The receiver itself, negligible, maybe 0.05A, ESC is negligible as well but yes it needs power for the control circuit.
What else is plugged in? In my case I have 3 fans running, and they are each ~ 0.5A for a total of 1.5A (ESC, 2ea. motor)
Now, servo plus fans = 6.5A in this example. How will this work if the limit is 6A? Remember above where power must stay constant? The only solution is to lower the voltage (44W/6.5A = 6.7V)
Now comes the next wrinkle, the receiver must have a minimum operating voltage of 3V. For this example, everything still works.

Peak current is literally only for a couple milliseconds, it is only for the time the ESC will stay above the rated voltage (with tolerance).
It will collapse quickly thereafter. 44W/25A = 1.76V and outside the normal operating range for the receiver.
That is 'brownout and dangerous as electronics are no longer fully predictable as to how they react. Random signals or just standard shutdown will occur.

Other bad stuff happening, as the BEC voltage drops, the attached loads will increase their current draw to maintain their power level (all within their specific limits) and all of a sudden you start having a small avalanche effect, and you are quickly in a brownout, again we are talking less than 1s.

Not included is the heat being generated, the BEC voltage degrades quickly once above the rated current. Hence, you do not ever want to run close to max current on a continuous basis. You couldn't run the mentioned fan setup in a crawler where you are against stall current over extended periods.

Now if your servo is bad to begin with, like many of the Spektrum servos, they draw enough current to melt their internal wires ~ 10A. Plenty of brownout examples on this forum.

Ok, post is already too long 🤪
 
jkflow said:
Brown out.
Short version: When the BEC goes below the rated receiver voltage, bad stuff happens.
Your BEC circuit in the ESC can only provide a certain amount of current at the rated voltage. For a Max6 it's 6V/7.4V and a cont. /peak current of 6A/25A.
The 25A peak is misleading, but I'll answer below. The magic formula here is that electrical power will stay constant. 6V*6A = 36W or 7.4*6A = 44W

Everything you plug into the receiver draws current. I could not find any info on your Ecoboost, but these are typically in the 4-5A range, they draw more current at higher BEC voltage (higher torque). That is worst case.
The receiver itself, negligible, maybe 0.05A, ESC is negligible as well but yes it needs power for the control circuit.
What else is plugged in? In my case I have 3 fans running, and they are each ~ 0.5A for a total of 1.5A (ESC, 2ea. motor)
Now, servo plus fans = 6.5A in this example. How will this work if the limit is 6A? Remember above where power must stay constant? The only solution is to lower the voltage (44W/6.5A = 6.7V)
Now comes the next wrinkle, the receiver must have a minimum operating voltage of 3V. For this example, everything still works.

Peak current is literally only for a couple milliseconds, it is only for the time the ESC will stay above the rated voltage (with tolerance).
It will collapse quickly thereafter. 44W/25A = 1.76V and outside the normal operating range for the receiver.
That is 'brownout and dangerous as electronics are no longer fully predictable as to how they react. Random signals or just standard shutdown will occur.

Other bad stuff happening, as the BEC voltage drops, the attached loads will increase their current draw to maintain their power level (all within their specific limits) and all of a sudden you start having a small avalanche effect, and you are quickly in a brownout, again we are talking less than 1s.

Not included is the heat being generated, the BEC voltage degrades quickly once above the rated current. Hence, you do not ever want to run close to max current on a continuous basis. You couldn't run the mentioned fan setup in a crawler where you are against stall current over extended periods.

Now if your servo is bad to begin with, like many of the Spektrum servos, they draw enough current to melt their internal wires ~ 10A. Plenty of brownout examples on this forum.

Ok, post is already too long 🤪
Click to expand...
Thanks for that info. Based on what you wrote, it's also possible I browned out the first time causing the fire. I was running 5 fans and two separate sets of lights. The lights and body fans had wiring melted out, so I've ordered another 2 Rockets 32k. I'm going to look into a separate 2s battery to take some of the load off the electronics. Since I want lights switchable, makes sense to run fans on separate battery for constant running
 
Yes, that would make sense as the servo only consumes high current when it's active, definitely a possibility.
I'm stretching my luck with 3 fans and a 5A BEC but my fans have less current draw. Right at the edge for myself.
5 is too much, no matter what fan combo you use.
 
Idle amps alone can be very high depending on the servo. And a servo that is failing will pull excessive amps under load or at idle.
Make sure BEC overhead can handle all that's plugged into it. Just food for thought.
 
Guys, there's a reason for the Glitch Buster on the ProModeler website. On RC cars and trucks, one plugged into a spare channel on the receiver puts you in tall cotton. Model airplane receivers? Different story, just Google the RF brand (the radio frequency brand, e.g. Futaba, Spektrum, etc.) and the word 'brownout' and you'll soon see if your favored brand is known for brownouts. Bad juju follows, believe me.

No open channels? Then use a Y-harness and parallel the load and the capacitor (what Glitch Busters actually are). And if you don't want to buy one from us, no huhu, ours is just a 4700mf 16V low ESR capacitor. Low ESR is the important bit if you're buying them off Amazon to roll your own. Way it works is, as the voltage dips the cap discharges into the circuit. Then once voltage is back to normal it recharges. Otherwise it just sits there harming nothing. There's absolutely no downside (other than the 5 bucks out of your wallet).

So why can you walk into a hobby shop and buy a capacitor by asking for a Glitch Buster? Simple, maybe 15 years ago when 2.4GHz radio systems became really popular many of them would brownout under load. When a receiver browns out, it's essentially rebooting (turning itself back on). That's when the servo will usually glitch (as the receiver comes back to life and re-centers the servo). However, with the capacitor goosing the receiver during the voltage draw down event, there's no glitch, hence the name, Glitch Buster!
 
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A glitch buster is a Fix when something is awry. And it doesn't always work. These caps have been around for many years.
A not so great amp hog for a servo, or a poor ESC BEC amp rating. Basically mismatched components. I have used them. One is in my MT410. A Savox amp hog servo. And that servo came with the Glitch Buster. What does that tell you? Savox knows it is an amp hog.....
99% of servos never come with them or even need them. Many amp hog servos are pigs just while Idle.
 
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Not a friend of glitch buster type setups, but they do help in limited cases.
They will not help (and never be able) in case of brownouts, i.e. longer periods of under voltage (anything above ~0.001s if it's a beefy cap). They typically can only filter out noise in the micro- second range (thats 0.000001s), that is what they are meant to do, and they are good for that type of problem.
Those could come from fan noise etc, but I'd rather dispose of those type setups. Never had issues with those little rocket fans.
 
fish said:
That'll Buff right out!
Click to expand...
It did! Amazing buffer and I recommend it!
20220530_214059.jpg

Same rc, and only 2 buffer swipes!
 
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