True, has it’s own shortcomings.
I’d say: momentary > 0v battery > getting run over because you can’t brake.
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Agreed
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From the above link:
- Power button type: latching button
So the dual Ubox uses a NC momentary button switch (what you told me via PM) but the single uses a NC latching button?
Or is it just that the single also supports the use of a latching button, same as the double, and we can still use a momentary button for the single too?
Can I get this to do “roll to turn on” if the wire is added like on the vesc6
John have considered this problem in design, the reason we choose latching button is because the board is no enough space to put an momentary button mcu. he reserves the power circuit, considering to make it momentary support by firmware
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currently single ubox can’t support a momentary now. due to limited space and urgent time, John will consider to make it fixed by firmware , also we’re waiting for first 50beta version feedback, then we can fix all (if there is other suggestions) in formal mass production version. This is our plan.
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NOPE. THIS IS A BAD IDEA.
This weekend I watched an evolve hadeon have its latch fail to the off position from a small impact (tire to deck) with another board
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I’ve also had a latching button turn the board off when I hit large bumps.
Rocker switches would be the same electrically but better in that regard, though flying debris can still turn them off.
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it’s in stock, can ship soon.
Hi, Guys, today we launched a new stuff. please check if you need it . keep safe during brake or downhill.
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What happens when braking exceeds the 10a peak braking current?
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I would guess it goes into the OVP but I’m an imbecile. Let me dig into this.
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it actually supports 20A. It’s a different concept with braking current.
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Can you please explain? I get stating lower rated currents then it can actually handle but let’s hear this concept.
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Even still, 20A is a small number.
Is the unit just bypassed if braking current exceeds 20A? Or does it just get really really hot? 
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I love fires! 
It appears that this unit starts diverting current into a resistor you connect to this board, the classic rheostatic load method. The (average) amount of diverted current depends on the resistance you connect and the duty cycle of the MOSFET that is sending current to the resistor.
At 4.19V/cell (ideally) there is no diverting of current. At above 4.20V the MOSFET is switched on/off via a PWM signal created by the board. At 4.20V the PWM duty cycle is 0% and at 4.328V/cell the duty cycle is 100%.
So be aware that if you do a lot of downhill runs your cells could be at 4.328V for a while (assuming a balanced pack). You may want to adjust the voltages if this is the case as that is a high voltage for cells to be at more than once in a while.
If your setup is not handling the bulk of the regen current then, of course, your cells can rise above 4.328V. That’s just the voltage where this board is full on, diverting as much current as it is set up for. Whether your voltage keeps rising or not depends on your pack, its voltage, your regen setup, and how often or long you are generating regen current.
If you have a resistor that allows 20A to flow at 4.328V/cell that seems to be the max that can be diverted according to Spintend. If you have 40A of regen current then 20A of it will still flow into the pack (and 20A through the resistor).
There is probably an overall duty cycle for regen at levels above their 10A rating. That is, you could do a continuous downhill run at 10A of diverted current (into the resistor) but only occasional regen at a level of 20A into the resistor. Testing would be needed to determine this or Spintend could comment on this.
If my guesses at what the 10A/20A ratings mean are true then if you needed to divert more than 10A continuous or 20A occasionally then you’d have to use two or more of these units in parallel, each with its own resistor. This is a perfectly legitimate method of handling more current than one board can support.
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Thanks John!
What I don’t really understand tho, is if the current is more than a single unit can handle, how it just ‘overflows’ into the battery.
But I am incredibly inept with matters like this so please be gentle on me
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Think of it as a big pipe to the battery with “water” coming from the motors. By adding this board you are just tapping into that big pipe with a smaller pipe to divert some of the water flowing through the main pipe. This small pipe might not be big enough to divert all the water so some continues to flow to the battery.
How much gets diverted depends on the resistor you choose (limited by the current rating of the board).
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