I can’t help further until we have those answers
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My unity power button went bad. How can I bypass it while I wait for a new one? I know how to make a loopkey (duh) but I don’t know how to make the unity turn on right away after getting power. Thanks in advance!
I just rode my board and it seems that it shuts off under these specific conditions. I am at 60% battery and going full throttle up a hill. It cutoff once at a not so steep hill for one second and I got connection back. The second hill I went up was noticeably steeper and when going full throttle, the board shut off.
short the button pins… enable roll to start, and an appropriate board shut-down time out and you won’t need a loop key… or a button…
(however roll to start may require the board wheels to be spinning for a bit, some motors require a bit more of a spin-up…)
one board, I have to skate down a sloped driveway, another I can spin a wheel by hand to energize roll to start
hit @CiscoV he may still have some unity buttons…
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Yea it starts out working perfectly and after a while the cutoffs start popping up until its bad enough to shut off the board
At 2p i’m almost sure you are hitting some sort of battery cutoff.
Here’s some problems to look into, from most important to least:
Try to read your battery voltage under load. You can only really do this by using a bluetooth module.
Find out what batteries you have inside that pack, find out if it has a bms inside and find out if your discharge wires go through the bms or straight from batteries.
If it is wired through the bms it is very likely to cutoff the power completely. People here don’t like running discharge bms for this very reason… it puts them in danger.
And batteries it is quite important to know their specifications and know what they can safely output. If it’s 2p 30q for example that is a maximum of 40A total.
That antispark looks iffy at best… my personal advice is to upgrade to something better, like a loop key (dirt cheap) or better antispark (expensive, around £40 i think)
And finally wiring… that looks like an unnecessary long cable and long battery cable has a low risk of introducing big voltage spikes though induction. The esc has some beefy capacitors on it but they can only protect so much.
So, a short tl;dr of what likely causes cutoffs: bms of the battery, battery itself, antispark
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What if I’m running the official VESC firmware that doesn’t allow for roll2start? Also which pins? I don’t wanna fry anything
Thanks btw!
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do you have a Unity pinout?
Tysm this is really helpful and I’ll be sure to check out all those points. Unfortunately I paid $70 for this antispark just to find out its terrible. I was wondering if I could just plug in the battery straight into the vescs to see if the antispark rly is the issue
I think roll to start is more like a mechanical feature… motors generate energy when rolling anyway. Esc turns on from that energy. If there’s an antispark that detects that, then the whole circuit turns on.
Sorry but i didn’t follow the conversation too far. I’m only answering to this
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Whoever sold you that, ripped you off big time.
Even the best antisparks around here don’t go for over £50
Don’t plug the esc straight into the battery. You will weld the connectors from the spark and you will panic even more if anything goes wrong.
Buy a xt90s connector pair, loop the positive wire through the male connector and connect the pins of the female connector with a beefy wire. Loopkey done.
There is a thread on this forum with detailed instructions and pictures for this. I’m sure someone linked it up here somewhere
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Will do. Thanks!
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@jack.luis
short the MOM pins
EDIT:
just checked, Unity running FW5.01, direct drive… one qwick hand-spin of the motor energizes the roll to start and turns the Unity on…
Don’t ask where I found roll to start in the VESC apps…
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I re-read a bit the recent stuff you said.
About battery cutoff:
ideally, between battery cutoff start and finish, your power will drop linearly and letting you know that there isn’t much left in the battery.
In reality a hard acceleration at 30% battery will likely get you straight to cutoff end, but because the linear decrease you will have a short burst of power and then you’ll feel it limping the more discharged the battery becomes.
I run my 12s3p at 33v cutoff end and 38v start, with the condition that i don’t run it until it is completely dead.
This lets me use the full battery accounting for acceleration sag and pretty much always get home with a little bit over 36v (3v/cell = empty).
I imagine your 2p battery pack sags even worse, for which you could drop the cutoffs down a bit, but again, don’t run it till it’s flat… it starts limping, time to go home
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Alright this seems like a good way to troubleshoot my problem. Ill give this a try and see what happens
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That is not the cause of the cutoffs however. The esc remains fully operational even past the cutoff end and you still have full control over the brakes.
When things shut down you gotta look from the battery up for problems, and i already gave you a list earlier
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yep… thanks… and others have already given some advice on his other thread…
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Sorry for creating the thread and basically spamming this topic. I was just freaking out in the moment. Next time, I’ll make sure to keep my problems in this thread.
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Sounds like a shitty battery then, or you have the settings too high. Either way, sounds like voltage sag from poor cells or settings too high. What is your “battery max” set to? Per motor, or combined? Those need to be no more than 30A total or 15A + 15A
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