Tb 6374. Motor max set at 60 which seems to be the limiting factor
Change âmotor maxâ to 80A
Any concern with the vesc? It is a tb 4.12.
Should be fine rated for 240A for a few moments or 50A continuous so long as you arenât at 100% throttle for a long time you should be fine.
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So I know the problem with most anti spark switches are that they donât have pre-charge, what Iâm wondering is if different voltages cause different amounts of damage to the anti-spark. Iâve talked with different users on the forum about their experience with this switch and have heard mixed results, although most people Iâve talked to are using 10s. Iâm running 12s, so do you guys think that the higher voltage would wear the switch out faster?
Donât have much experience with the mosfet based ones I just use a loop key or antispark plug between battery and VESC. My guess is the higher voltage could be above or nearer the limit of components on the antispark âswitchâ or PCB but certain mosfets can get hot if the gate is partially open or not enough voltage is applied to close the mosfet and activate the circuit.
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Charger recorded 364Wh going into the pack when it should have been 259Wh to top offâŚis that a concern or just how much vents as heat? Its a 28.8% loss
12s3p 30Q charging from 40.8V
So long as the charger isnât pushing the cell voltage much above 4.20V I wouldnât worry much about it either could be some miscalibration in the charger or like you said some energy bled off as heat and in the process of balancing cells.
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Charger is reading 50.65V out so thatâs 0.02V over chargerâŚshould be fine right?
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Yeah you might want to limit it to 4.1V per cell since you donât get much out of that first .1V anyway itâs basically instantly gone and wonât risk damaging cells from over charging.
Cells can typically take a little over charging but check out Alex Vanover in quad community for how over charging goes wrong 
. To be fair he way over charged but it is not great for the cells health/cycles and more volatile when highly charged.
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How would I go about limiting that?
It depends on the BMS or balance charger, with balance chargers itâs usually very easy for BMS Iâm not sure.
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Itâs some unknown BMS wrapped up with the pack
The capacitance is the main enemy in this scenario, not voltage. Although more voltage is more bad because it exacerbates the problem.
See this
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Youâre thermal throttling from the ESC, not the motor. Look at TempPCB vs DutyCycle. As soon as you exceed 80C (The default thermal limit), the duty cycle falls like a rock and you lose power and thus speed.
This is also a little more noticeable than the norm because youâre driving a big powerful motor with a not very big or powerful ESC, thus the ESC overheats before the motor is even hot, just warm.
The only thing I can really recommend is to somehow improve your ESC cooling and/or thermal mass. Neither is particularly easy with a 4.12 ESC though, so you wonât be able to make a ridiculous difference without taking extreme measures.
If you decide you need much higher continuous power handling capability, my only real suggestion is to upgrade to a beefier ESC with provisions for better cooling.
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The ESC definitely heats up quick, but what I donât understand is it looks like the speed and duty cycle hit a minimum before the Temp is above 50. The motor amps are maxed at 60, which is likely what is limiting. If I up the motor max to 80amps as suggested, this may put the esc over the thermal limit. I probably do need to upgrade the esc or go to a dual setup. I donât have a lot of hills in my area, so I was trying to avoid the dual route.
You are undeniably thermal throttling, and that is undoubtedly what is causing your hill climb to slow down at the end.
Upping your motor amps to 80 will improve your hill climbing, right up to the point that you start throttling, and then do absolutely nothing. In fact, upping your maximum current will almost certainly make your ESC heat up faster, so you throttle sooner.
The vesc is smart, it wonât let you overheat it to the point of failure - thatâs the whole point of thermal throttling - to idiot proof things so you canât melt your board by asking too much of it.
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This is an understatement, with 4.12 youâre basically stuck â as the MOSFETs dump the heat mostly into the PCB, not the exposed surface
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I was trying to hedge around it, didnât want to drop a âyouâre fucked until you buy more expensive hardwareâ bomb on a new builder. 
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