You could also drop in 1000A then. 70 motor amps are the limiting factor.
The usual scenario is that the motor power determines the necessary capabilities of your battery. If you don’t follow that rule and build a board with a too weak battery, then you are free to adjust to this constellation. The Tool warns you, that no battery limits are set.
In reality you will see voltage sag that goes against drawing more power.
Most people use big, beefy motors for better acceleration at low speeds, better braking, better efficiency, and lower temps. Few people have batteries big enough to power these motors at their max. Just saying.
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Why not just adjust it if the people are asking for it. Thats the simplest solution to make everyone (most) happy.
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make a t-shirt with all the rules so we know what they are 
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So your answer to “Please remove auto 99A” is “Go with bigger batteries”.
Is that some british humour?
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That’s why you get a popup warning and you are free to adjust to your battery’s capabilities. Setting a default guesstimated value, assuming an unknown battery is sort of funny.
And we’re all asking you to set that guesstimated value lower 
Or ask for it in the wizard, because it is quite important.
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and setting that unknown battery to 99A or 198a if dual is hilarious,
how about setting it to an unusually low number, to force the user to address it?
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No, where do you want to put it? 20A, 40A, 60A? There is no value that would make sense in general. People would complain why they lack power in the system. It would be random.
As a builder it’s up to you to drop in the correct value if your battery capabilities are below the motor capabilities.
100% it’s user responsibility to set the right value, but the value you get default should be safer
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40A I think would be low enough to save the lives of many ESCs. and -40A braking is more than any of my current builds have lol
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Motor amps are the limiting factor! Battery current can only be as high as motor current, no matter of the setting. If the motor current is 50A, the battery current can never go higher than 45A in reality. So a battery current setting of 1000A would not change that. And these 45 A would only flow at top speed up a hill. If your battery is not capable enough, you get voltage sag and the speed and amps reduce themselves.
definitely user friendly…not
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But sometimes vesc tool sets the motor current at something high like 70A. My focbox definitely can’t handle 70A safely! That’s why the 99A value is an issue.
Edit: in hindsight I shouldn’t have used the focbox as an example. same thing happened on my TB 4.12ESC, and that thing gets cutouts at 40A lol
Or just in general when accelerating to top speed with full throttle. Even on flat. Checked my metr logs, it do do that.
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Accelerating is limited in time and not a n issue really.
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Yes Beta 5.2 has it fixed now, but need to test a bit more for next release.
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I do get that, but it’s a change in default behavior most aren’t used to or maybe aware of. This gives a higher top speed than you wouldve gotten using previous default values, that could be dangerous
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You can push 70A towards the motor while only sucking 30 from the battery!
And I highly doubt that you can’t push 70A through a Focbox for some time.
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The focbox will simply heat up and throttle itself safely. The only possible way this 99 amps can be an issue is if you were able to setup a scenario where you could sustain that current out of the battery for long enough such that the battery cells were heated to an unsafe level while also not sagging enough to hit the voltage cutoffs. Lithium ion chemistry is pretty stable so its hard to push cells into this region but it could theoretically happen. In practice 3 things always prevent this
- voltage sag
- ESC heat throttling
- Skateboard too small of a load to ever sustain 100 amps at 40V for any amount of time
I do think ignoring the cutoffs completely is not a good idea in the wizard, but right now I think that the way it is handled in the phone app is solid and the tool is just at an acceptable level.
Vedder and I were talking about getting the phone app wizard working with the regular tool as well since it feels a bit more polished and then we have only half the wizards to manage.
I think the focus on the “default” value is kind of irrelevant as the nothing works out of the box anyways so these settings will need to be touched. If you are bypassing the setup wizard you should know what you are doing.
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You omit some elements : nickel strips, wires, fuse, BMS and so on.
Some other elements can be in a undesirable constrain that may heat up and accelerate the cells ignition.
(and from what I read it’s the #1 root cause of batteries fires).
Lithium Ion isn’t stable at all.
Anyway this “99A” stuff is an endless talk since it has been introduced.
I’m done with it (but will still need to answer endlessly to “My VESC Tool has a bug, it says 99A Batt Max !” 
)
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