MMX8S esc over heating

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Edough13 said:
You could but I figure more connections is more resistance but until your going for big numbers above say 150 it's not going to make a huge difference. But definitely suggest the G+ 70c packs they are the top performers for CNHL👍🏼
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I’m not trying to hit 150+. The goal for me was anything over 100mph was good for me. Afterwards I was going to stop speed runs and pull the speed gear setup out so I can bash. I just purchased a set of batteries today. I’ll post the results after I run them. Thank you for the help. 👊🏻
SrC said:
Yeah I have the LIM( with spool stock 34 and 27 pin ) You have the Infr. converted over. I went with a Tekno 28 pinion.
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@SrC I have the Tekno 30t on it, but I see the points everyone was making about it being geared to high and the lipo batteries not high quality causing my setup to pull more current. I’ll pick up a 28t pinion today, but I also ordered two cnhl batteries to try.
 
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Below is from radiocontrolinfo.com.

Over the years, with brushed or BLX systems, I always understood this a follows:

"When it comes to battery packs and motors, the biggest concept to understand is that a battery does not “push” power to the motor. Just because the 45C rated battery can deliver 180A of continuous power doesn’t mean it will. In fact, the load placed on the motor determines how much power is going to be drawn through the motor, ESC and battery."

"A higher C rating should not ever destroy any RC component. However, this does not fully mean that it is impossible. If the power system in your RC vehicle has not been correctly selected, it is possible that a component within your RC can fail."

I don't feel the lipo made your ESC Hot. No matter if it had an adequate C rating or not.
Gearing (load), Ambient temps, and driver throttle input (load) were the factors here contributing to high ESC temps.
 
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^^^ if that is true, The ESC is AMP cutting for sure. Combination of gearing load and Driver Throttle input.

Where is the log posted??
 
^^^
I disagree that low input voltage/current caused the ESC to overheat. Appears performance was not so much an issue. Just ESC over temps were his complaint.
Hope I understood the OP well enough. An inadequate lipo capacity and C rating for a specific setup will add to many factors. I just don't believe heat will be one of them.
A near empty can of gasoline is not going to fuel the fire anymore.:LOL:
@jkflow what is your opinion on this.

I still don't see the OP's logs anywhere.
 
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He did state that there was an overcurrent error on the log sheet.. and a cool calm 136 on the motor and 176 on the esc after several passes does not necessitate overheating, does it?Wonder if he got the 4 green pulses on the esc for thermal overload?
 
Yes exactly my point. amp cutting. CC ESC's are very sensitive to this. An ESC fail safe.
The overgearing and Dr. Thr input may have caused the heat.
Potentially 2 distinct and separate issues presented itself.
ESC Heat from load,
Amp cut from depleted lipo. A domino effect.
I have had amp cutting before without ESC hitting thermal. I also have had ESC thermal cuts without amp cutting. But both can occur together.
 
MMX8s does not cut anything due to current draw. I was regularly pulling over 400a with it no problems.
The Castle Link will show a warning about currents over 350a as a pop up message, but it does not restrict the current.

If he has never modified the settings it is likely hitting low voltage cut off or thermal. The MMX8s gets quite a bit hotter than the XLX2 but still does better that the old XLX, MMX6s, or MM2 ESCs.

We already established the education that you cant make 3+ speed runs without a cool down, so he is already more informed and well on his way (y)

As SrC noted lower C batteries and higher resistance in the wiring or connectors can lead to higher system heat.
 
SrC said:
Not really. I am def. not an aficionado with CC esc's.
I have no CC stuff here. Yet.
:cool:
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Well you'll have a jump ahead, if or when you get some CC stuff. But it's honestly just general to all esc's just some cut out due to Amp limiting such as the hobbywing or spektrum where Castle does not Amp limit and why it's the most used for speed runs.
 
Edough13 said:
Well you'll have a jump ahead, if or when you get some CC stuff. But it's honestly just general to all esc's just some cut out due to Amp limiting such as the hobbywing or spektrum where Castle does not Amp limit and why it's the most used for speed runs.
Click to expand...

Just for information purposes I would add that Castle does not amp limit on the following ESCs.

MMX8s
XLX2
MM2 Retro

All the others do have amp limiting.
 
^^^I just learned something.
What about the older XLX? Limited also? I thought all were the same.
Live and learn.:)
 
SrC said:
^^^I just learned something.
What about the older XLX? Limited also? I thought all were the same.
Live and learn.:)
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Yes it had amperage limiting although its up around 400a and was plenty for any 40mm diameter motor.
 
Everyone thank you for all the comments and help so far on this issue. I was working late yesterday and didn’t get to put the log in the chat. Please be patient as it will take me a few days to get back to this due to my work schedule and kids sports events. I should have something up for us to analyze by Friday. Let me try to clarify some questions I read in previous responses.

1. The gearing is 30t pinion / 34t spur ( limitless spool)
2. The motor wires are stock length and are free of kinks.
3. The battery connectors are Protek QS8
4. The esc soft aware has current update.
5. The esc motor temp was raised to 190, zero drag brake, 70 regular brake, motor reversed, lipo cutoff 3.2v, zero punch control, throttle & brake curve is factory settings, auto lipo cutoff.
7. Perfect pass carbon fiber drive shafts.
8. I did get an audible alert but can’t remember what the it was. I did have my temp gun and external of the motor and esc were close to the internal temps I originally posted.
9. Stock Hoon tires from limitless
10. Gear mess was perfect between pinion/ spur.

The photo was before the battery connectors were installed.

A3F9493F-50F9-4527-9FBE-9BDAA874313E.jpeg
 
ESC settings are pretty much good for your setup.
You dropped your temp cutoff to 190 at the ESC? Confused on that one. I understand why you did though.
Great that punch was dropped all the way. (for speed running) Many overlook this.
F/W is current. Not being familiar with CC, any specific issues addressed with that latest F/W (April 2021)? Aside from The D wind large motor issues.

Edit:
Hopefully you are in Smart sense mode (by default should be). What is your timing set to? I believe 10 deg is "Normal "." Sensor lost Warning" should be enabled. As recommend by CC.
You said you are not getting any audible tones?

https://www.castlecreations.com/img/product/description/Error Tones X Series ESC 032618.pdf

Data logs will help. When you get a chance.(y)
 
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You could always try dropping your timing down a notch and evaluate any change.
98F there in Tx is pretty dam hot IMHO.:LOL:
 
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