So Flipsky just contacted me and told me that the shipment of my antispark was pushed back to monday for production reasons. Looks like i’m not getting one of their preliminary samples after all. IDK if that’s a good thing or a bad thing.
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No pre charge on that.
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My anti-sparks are built into the ESCs, I feel like this should be the case for every ESC. Plus, these ESCs can push 30V 160A each.
Which esc? The unity one has proven decent but the flipsky and maytech ones leave a bit to be desired. They will eventually all pop right?
What if you wire in the antispark AFTER the capacitors?
Nothing happens, it works like a switch that precharges your ESC. I have regen (60 Amp) on my eBike, works fine. And (12 Amp) on my eBoard, works also perfectly. No Issues.
Just as always watch out that you have a overcharge limit set on your vesc (and dont break strong with a fully battery), so you dont destroy your eBoards.
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Its a toggle switch. Not momentary. If sw+ and sw- are connected to each other your Board will turn on, and if you disconnect sw+ and sw- from each other the Board will turn of, just like a switch but with precharging
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I got an eMail with a question so I thought I should also mention that here since people are wondering why Antisparks Break on high power ESCs.
Explanation is really simple: Your mosfets have a maximum peak current (300A per usual Antispark Fet), because current creates heat and a high burst of heat can destroy any mosfet.
What happens when you connect the wires of your VESC to your Battery is that a uncharged Capacitor basically acts a a short circuit as long as its not charged.
So when you just switch on Mosfets you will create thousands of Amps burst for a few milliseconds. Enough to cause a “Latch Up Effect” https://en.wikipedia.org/wiki/Latch-up
The insane heat causes the Mosfets to stay always on.
I expirienced that many times, and got tired of it so I tackled the Issue.
This is my working PCB design of that. When you switch my Pryside Antispark on, first over the big Resistor the Capacitors of your ESCs will get charged, after 300ms the big Mosfets get activated.
In that time, you can charge a 100.000uF Capacitor bank and still be safe that your mosfets will not get blown.
Have seen many people use way too big Antisparks, because manufacturers just added tons of mosfets in parallel to delay the eventual death.
This thing saved me so much hassle. I had blown Mosfets before that every few weeks.
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When normal use, energy goes from batteries to esc and to motors… But when regen, it reverses… And the antispark sw is in between… Afaik, mosfets are the one way switches that, in antispark structure, allow a current flow from batteries to the esc and motors, not the other way around
MOSFETs are bidirectional, their internal body diode only allows them to block voltage in one direction. Back to back MOSFETs congiured in common source configuration are required for blocking voltage in both directions.
The issue with the inrush current is not latch-up, that is a completely different phenomenon, and only happens with that garbage known as HEXFET, modern power MOSFET technology is no longer susceptible to such failures. The thing that happens here is pure thermal failure in the MOSFET, the thermal shock breaks down (changes the chemical properties of) the blocking pn junction and causes the silicon to become a short circuit. A lot of heat is dissipated because for a brief moment, the MOSFET must dissipate the inrush current at full load voltage.
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yes and no. Have tried other mosfets and its just a matter of how many times you try. Maybe on setup with a single vesc this works fine, but I have some high capacity ultra low IR caps and on my Kelly Controller like 10mF of them, and I couldnt find any fet that would turn that ESC 1000times in a row on and off (I’ve let a arduino do that for me) without dying.
Its just not safe turning any Mosfet on with a quick current burst that is way above spec.
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I chose a value of 220n for C1 and 470k for R1.
This results in a dV/dt of about 100V/s
Multiply this by capacitance to get inrush current.
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Ah thank you very much brother.
Edit 1: and thank you @Gamer43 for the knowledge, I have a pile of Maytech VESCs with ‘anti-sparks’ that don’t work and now I know why.
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Old school HW Max6’s! 
They even brake with full batteries!
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Hey there… In my days I ran through 4 of those Anti Spark Switches… I repaired 3 of them but the common defect is that the MOSFET gets a Drain to Gate short and is always on.
Since I can’t trust those switches anymore I will also go for the less visually appealing Loop key.
In the End its also a safety concern.
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How is it running so far? 
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Perfectly. I see nothing going wrong with this one.
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My pryside died within a couple runs, diode shorted to either Bat+ or Bat-, think it was just a bad initial soldering job, killed 2 of my VESCs, no longer trust Prysides antisparks.
That sucks dude. Mine is a soldier. It’s probably never going to die.