v3.1 only has a 400micro-amp draw at 84V when turned off. This is very low and would take over 2 years to drain a 8AH battery assuming no other sources of discharge. I would suspect something else in your system is draining the battery in a matter of weeks.
Also, anti-spark isn’t needed with either latching or momentary on/off buttons.
Wow, I never knew that. Is this a difference between v1? I know for that one it was said I need antispark, assumed this hasn’t changed…
As for the drain, that observation is also with a v1 FOCer, and a used Pint battery. I haven’t yet had my FOCer v3.1 board lay idle for that long that I’d need to watch the voltage. Again, poor assumption on my side I guess…
Oh yeah! Big differences between v1 and v3 lol. Many improvements including the drain when turned off.
@shaman I know it was mentioned that the Little focer V3 is not possible to have a momentary switch. It is really impossible? I mentioned that because I have seen how the ubox with a proper update make the momentary switch to work, so no need for latching switch. Is completely impossible because of the hardware or because will not be supported even though could be done?
I mean, a momentary switch for the little focer v3/3.1/3.1.1 should be a great feature IMHO.
Thanks
Any idea on when the v4 will be ready?
It is not possible to make momentary switch work for v3.x because of the hardware. I know it’s a highly requested feature hence why v4 has this compatibility.
starts production this month
What’re the specs on the V4? Any increases in performance and form factor?
Same form factor but several improvements and new features.
Hi @Relys, does WS2815 with little focer works for you? I’m thinking of doing same. Is the pin6 working for ws2812 signal? Are you using this on a onewheel with float package?
Hey guys, first post.
Some prerequisite information, I do board level repairs for a living so I’m quite comfortable doing circuit troubleshooting and repairs.
My FOCer 3.1.1 suddenly stopped working today. I was doing some work on my led setup simplifying the wiring. The LEDs are essentially entirely separate from the FOCer (minus an Rx and Rx connection). The FOCer was unplugged from the battery, and while repining some led wires I head a small pop like a spark/arc. I stopped because I wasn’t sure what it could have been, everything was unpowered.
Finished up my wiring and reconnected power and it doesn’t power on. No lights, 5v rail is a bit above 1v, no 3.3v. USB connection is the same result. The only thing I could consider was my 3 pin footpad connector (adc 1 adc 2 and gnd) may have touched a connector that had battery voltage present. If this is the case, what may have died? I can’t visually see anything burnt.
I appreciate anyone’s help here.
Sounds like you shorted the 5v rail.
I had a bad high side switch that caused a bunch of damage when it failed. Took out all kinds of stuff.
suddenly stopped working is pretty different from there being a pop and then things aren’t working. For there to be a pop/arc, something would have had to have power.
What exactly is your lighting setup? What’s the wiring path, and what was left connected?
If it’s entirely separate except for the Tx and Rx of the UART port, then even with the FOCer disconnected from power, your lighting setup could still be powered?
Since the UART pins are just data, it’s likely something was still powered, and shorted on the 5v power source somewhere.
I’m right there with you, I understand something must have shorted. It wasn’t a loud pop, so I questioned if it was even electrical related or possibly just gravel or dirt crunching under my rear foot pad. I haven’t had any issues with this board up to this point.
My lighting setup is exactly as your article describes with the meanwell buck converter and Arduino nano. The only plugs connected to the focer was the Rx tx connection to the Arduino, motor phase wires, power button, and the foot pad 3 pin wiring.
The focer was completely unplugged from the battery, the buck converter was unplugged from the battery, and the charge port was unplugged from the battery (BMS), nothing in the front controller box had power, except for the unplugged power leads themselves from the rear box.
The only thing I could see as possibly happening was my three pin connector for the foot pad possibly touching one of the battery connections that had been unplugged, meaning one of the ADC lines may have briefly touched the positive terminal of one of the xt60 or xt30 connections.
If you started repinning right after disconnecting power, there could have still been charge held in the input capacitors maybe.
It is possible, though the wires I was repinning when I heard the small pop were on the LED strip side and completely disconnected from everything else in the system, hence my confusion.
The only thing I could logically come up with after pausing and looking at everything was my 3-pin footpad connector somehow touched the XT30 power connection which was unplugged from everything else, touching that exposed contact. Even that seems unlikely because it’s a female connector and the the odds of that finding its way inside to touch that contact seems extremely slim but I can’t see any way something could have touched something powered.
I’m interested to see what shaman thinks, if shorting one of the adc lines to battery voltage would take out the 5 volt regulator or surrounding protection circuitry.
I’m assuming the 3.3v rail is derived from the 5 volt regulator which is why neither work at the moment, but that’s just an assumption.
Yo! So yeah shorting the battery to the 3.3V rail then most likely shorted out several 3.3V components like the STM32. Even the protection circuitry on the 3.3V rail most likely wouldn’t be able to tolerate that. With the LFOC unplugged from the battery, You can take a multimeter and measure the resistance between a 3.3V pin and ground to see if reads as a short or low resistance. If so, then it that is causing an excessive load upstream to the 5V regulator and would be why it’s only reading 1V or so.
Thanks for the reply, I’ll check the 3.3v rail when I get home today. In regards to the ADC lines, what can I check with those to see if it ended up being one of those that I shorted to Battery+?
On a sort of related note, any estimates on when the FOCer v4 is coming to market? 
I’d hate to buy another v3.1 if the newer hardware is right around the corner. Looking to buy another controller to have on hand as a spare anyway. I guess if anyone has a v3.1 they’d let go for the right price I’ll take that.
