2.0 right?
Brushed 60v 50a battery. Still pretty fun.
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hey Shaman, can you send me a link to buy 750
thanks happy memorial day
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yea its pretty hard to buy these I think - lead time from alien rides for 250 is 6 months and tronicsystems.com does this thing where you have to contact them through the website to get an invoice - havenāt been responded to in about a week - anyone else running into this issue/ where did yāall buy yours?
happy memorial day
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The 750 isnāt available just yet but it will be soon. I canāt talk much about those and this is a thread for the Little FOCer.
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Itās definitely being considered. I just gotta test it and come up with a solid method for the mechanical bond between the cables and terminals
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Would be awesome if this was possible. Iāve been considering some sort of FOCer/tronic for a bike build. Since itās probably just gonna be 16s, maybe the cheapfoc3 is the way 
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Iāve been enjoying great performance from a Little FOCer v3 running 5.3 on a hub-motor ebike for a few months but Iām experiencing strange behavior now.
I was using regen while descending a hill and it looks like the BMS disconnected, likely from overvoltage. Now the motor has very little torque and lots of vibrations and cogging on throttle and braking and the duty cycle jumps around erratically. However, the motor spins up and brakes smoothly if the wheel is unloaded on the stand.
No values in the motor configuration have changed significantly. Power cycling, rerunning wizard detection, and bootloading the firmware again donāt resolve the issue. For a brief inexplicable moment, the torque and braking were strong and smooth and then the choppy behavior and erratic duty cycle returned.
Any thoughts on how to further diagnose or resolve? Does the erratic duty cycle reading point more to hardware or software?
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This is a bad situation where the regen energy suddenly has nowhere to go due to the BMS disconnecting. This can lead to damage anywhere between the motor and battery.
It is very important to properly set the regen battery current to a threshold that your BMS/battery can properly tolerate. Also keep in mind that fully charged battery is simply not able to accept much regen current without risking a voltage spike or damage.
This sounds like maybe one of the phases isnāt being powered. Motor detection isnāt using all 3 phases for itās R&L detection process and a misfiring phase wouldnāt be as noticeable unloaded especially when you have a lot of poles (ebike hub motor) to help smooth things out. Then once loaded, the issue becomes apparent. The erratic duty cycle at rest is another clue that a phase is electrically disconnected for whatever reason.
My guess is that one of the phase legs in the controller took damage. Either a MOSFET or the gate driver or both took damage from the sudden disconnect by the BMS and the inevitable voltage rise on the bus led to damage. Thankfully it doesnāt appear to have failed short which is significantly more destructive.
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Agreed, would rather have controller shut down than have BMS disconnect and cause spikes. Will set better limits in the future and advocate for a regen current rollback like ASI does.
I scoped the high side and low side FETs by putting a probe from V- or V+ to each phase and then used the handbrake or duty cycle to brake or motor the wheel. They are all showing clean square waves in both brake and throttle. Does that suggest FETs and drivers are operating properly?
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Actual debugging with an oscilloscope? I see youāre a man of culture.
Try the same technique but measuring across the drain and source of each mosfet. This will be a better assessment of each mosfet. you can also measure the resistance between drain and source of each mosfet when the controller is disconnected from the battery. They should all be very high resistance and read as an open circuit.
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top secret invertersā¢
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Drain-Source probing also looked perfect.
Everything is working great again after reseating motor connectors. The problem appears to have been a flaky motor phase wire that cropped up at the same time as the apparent BMS high-voltage disconnect during regen.
Lessons were learned, foreheads were slapped, scope probe ground springs were used.
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Well at least you used proper probing! Glad the issue ended up being easy solve.
Any updates or ETA for the new little focer v3? v3.5 maybe? 
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The v3.1 is in production with the hopes it will ship out to distributors this month!
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Distributors? Who is distributing?
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Same ones as before!
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Oh I thought those were your sites.
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