The lower current addresses that.
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Come again? Unless youâre scaling your power ceiling, lower voltage will result in higher amp draw.
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The Rds(on) heat dissipation is not affected by the voltage, but only by the current flowing through the junction. The effective voltage across the FET can be computed from only the current and the Rds(on).
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Sorry, I forgot to add a snarky âCome again?â to my post.
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But running higher RDS(on) mosfets at lower voltage will pull more amps through them than at high voltage, thus increasing heat. Youâll run more efficiently and cooler at higher voltage to spec.
Iâm not sure that recommending people run 12S on HV ESCs for added reliability is accurate. Thereâs additional voltage ceiling there to make transient spikes a non-factor, but Iâm yet to pop a 60V rated ESC running at 12S due to a transient. If anything, heat has been the primary concern.
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Actually, an increasing resistance will lower the current draw.
I also recommended lower voltage AND lower current, not increasing one at the expense of the other.
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At the expense of heat. And I think youâre missing that this is a current controlled AC power system; what youâre quoting isnât actually applicable here. I can explain further if youâd like.
Ultimately if you want reliability, heat is your number one enemy. Transient spikes are a critical random event, where heat will slowly kill your components over time.
Lower amps = lower heat. You can lower your current draw by lowering your power ceiling, or raising your voltage.
Running an HV ESC at lower voltage only gives you additional protection against transients, and puts you in a worse position when it comes to generating mosfet heat.
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I am saying that less current is less heat. So you ideally want more voltage headroom and less heat combined together. This will increase reliability and decrease power.
Running an HV ESC at lower voltage and lower current puts you in a better position when it comes to generating MOSFET heat.
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The same settings with a 12S ESC will produce less heat due to the difference in RDS(on). Transient spike risk is reduced with lowered amps and not really a huge issue with modern 12S ESCs even at full charge.
FWIW: my position on this comes from both the electrical theory backing it + 18 months of riding on HV ESCs at 12S. They simply run hotter than the same setup with 12S ESCs, and the difference in mosfet resistance is significant. @Blasto mentioned this early on when I was building out LoveChild, and I decided to play guinea pig.
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Youâre right about ârun it at lower voltage and current to be saferâ, obviously, but
this is only true for a passive circuit with a linear voltage source. Ohmâs law doesnât work directly for nonlinear circuits where the input is controlled to hit a target current output. The target current will be hit regardless of RDSon, unless it hits another limit first.
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Yes, but then the extra voltage headroom isnât there.
You can have both⌠âŚsince you have a convenient control to turn down the heat.
Simply turning down the battery current will also turn down the heat.
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Excellent explanation.
I guess my point is that Iâm not sure the voltage headroom is needed anymore. 2-3 years ago when ESCs were less reliable, perhaps. Running a 12S ESC @ 10S? Sure. But Iâm yet to pop a single ESC from transients and I run 12S @ 110/85 motor/battery amps on each side for 10âs of thousands of miles at this point.
Im not sure additional protection is needed there, especially if it comes at the cost of a hotter ESC. Running 12S on an HV ESC will produce more heat at the same settings than a 12S spec ESC, 100% of the time. Heat is the enemy of electronics reliability.
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It doesnât come at the cost of a hotter ESC, there is a control (battery current) that turns down the ESC temperature. Simply donât set it high. 
If anything, it comes at the cost of power.
You can have both, as long as super high power levels arenât needed. Nobody drives Top-Fuel dragsters when they want reliability, they pick things more like a Toyota Corolla, and they donât drive it at top speed.
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Yâall above my pay grade, I can reccomend the stormcore 60D gets the job done for me (so far)
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Same here, but still amusing to see someone presenting opinions as facts get schooled. 
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Eh, my daily riding settings and 10âs of thousands of miles would beg to differ. I regularly push 3-5kW through that drivetrain. My builds last until I decide to break them down and rebuild something else. Havenât had a single failure that I wasnât intentionally pushing for.
I feel like the goalposts have been moved a few times now. I think a properly specâd ESC is the wiser choice, rather than having lose power to compensate for an improper voltage spec.
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I love it when you two talk and no insults are flying around. Maybe itâs just too early for happy hour tho
So I am good with a pair of TB6 VESC no need to buy a Ubox VESC to run 12S
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Not trying to take shots at you here but the initial question was âhow to get reliable VESCâ and the answer given was âbuy a big one and use conservative voltage and current settingsâ. Thatâs a pretty clear, and logically correct, answer. Yes youâre using less power but thatâs the idea, buy bigger than you need rather than redlining if you want a safe bet. Itâs not the perfect solution because of the cost, but if your concern is reliability it could be the right solution
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Happily running a pair at 12S.
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