As a thought with the trampa VESC 6 mark 3 having a hibernate mode as well as unity and flipsky switches on ESC will the flex light be able to activate hibernate when it detects the vesc has been turned off or entered hibernate mode? Same for when PTS will that trigger a wake up in the BMS? I’m presuming this would be a software thing. I know the DieBieMS used the 5v from the VESC back EMF to a extra pin on the BMS to turn on for PTS
Moro Simo,
Is it anyhow possible to join the party already?
Might there be someone who got one but does not have the time to test it?
Same here. If there is a spot open, let me know.
Get in line folks I think I’ve got first dibs 
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I guess I am in line now then ^^
What is their eat cost?
Hello and happy new year people!
I’ve been having my winter holiday and taking a step back for a moment from the project, but I’m starting to reactivate for 2020 now.
I have 0.5 HW coming up and I’ll be updating the designs and ordering the boards in the coming days for prototype units (most likely just one or two, no tester boards).
I have been looking into getting my LLC started. I’ve been thinking of possible names for the company that would make sense and would roll off the tongue, without the tongue falling out of your mouth. I don’t want to name it after specifically for esk8 business, because I want to sell other use electronics there as well, so I’ve been thinking of something like FinncoTronics/FinnkoTronics or something like that as other flextronics, hobbytronics names in that line were already used by someone else.
I’ve also been looking at local accounting firms for bookkeeping and reading up on what I have to do on my end.
I have a couple of local pcb&assembly fabs checked out to ask quotes from. I plan for a prototype production batch of 50 boards. Can’t really say anything concrete about the possible sell prices yet, but most likely for the prototype batch I wouldn’t expect anything under 80€ per board at this point, maybe a bit more to offset costs, but once the design is once again proven, step to higher volumes and start getting better bulk component prices and lower pcb & assembly costs per board.
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what have you founded out from the testers of the 0.4 batch? new features or inproving reliability?
For your legal structure: you might want to look into Estonian turnkey business structures, they also work well with Finnish bank accounts (you’re in Finland?).
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HW layout changes, meant to improve pick&place assembly and reflow performance with a couple of the more trickier packages, so in a sense, yes, it’s to improve reliability, by improving/helping assembly process.
Yes, I’m Finland.
I haven’t heard of this before, but I took a look at Xolo for an example, but it would seem that the service is more suited for purely digital goods, whereas I will be dealing with physical products.
Also I will be most likely making physical acquisitions in Finland and I don’t see how this business structure is going to work at that point. Most of the Estonian turnkey business solutions seem to rely on the Estonian e-residency and while it might work well for fully digital goods freelancer/entrepreneur. I suspect it’ll start to become PITA once I start to buy more tools for physical use.
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That’s their main audience, but they also have other types of services. Or Holvi might be an option.
It has been a while since I looked into it though.
Update.
0.5 HW is nearly done, but I want some feedback for one thing from you peeps.
silkmasks not updated yet
There was talk about CAN and wiring with the VESCs in the tester group chat. So I presented the idea of switching up the connectors a little bit to make it an easier wiring setup to connect to a VESC CAN bus wiring setup specifically with the addition of ability to wake-up the BMS when the VESC gets powered.
Current connector setup:
Currently the idea would be to just hook up the CAN connector to the VESC with the CANH, CANL and GND. This does introduce one problem though, which is if the BMS is in it’s low-power states and it has the CAN IC powered down, how do we wake-up to an active state if the CAN bus has traffic moving in it?
Couple different ways to do it.
First would be to power-up to active state every couple second and see if there is any CAN activity, if not, go back to low-power state, if yes, stay active for a set time from the last received CAN message, after which go back to low-power.
Second would be to use the 5V available on the VESC’s CAN-connector and wire that to the opto-isolated enable input, which can be monitored even in the low-power state. When the VESC gets power it then also activates the BMS and we know to start monitoring and sending CAN-messages on the bus.
Now, the first option would be purely software solution and is easy wiring wise, but it would also means that the low-power state average current consumption is increased, as we need to pop into active state every once in a while + once VESC gets powered up and starts sending CAN-messages there might be a short delay before the BMS wakes up and starts sending its info as well. This does however leave the opto-isolated completely untouched and it is truly isolated from the system ground, so completely floating signals can be used to wake-up the BMS.
Second option needs a bit more complicated wiring setup, as you need to wire GND and +5V from the VESC to the opto-isolator input, which means splicing wires in the harness and Y-joint for the GND wire. But will result in lower low-power mode current consumption and simultaneous wake-up when the VESC’s 5V gets powered up.
So what’s the proposed change?
We change the BMS’ CAN-connector from 3-pin to a 4-pin and add the opto-isolator input to the 4th pin. Now we can wire the all 4 pins from the VESC to the BMS without the need to splice the wires (wire order on the connector might need to be changed though, but that’s easy on the PH-connector) and wake-up happens when the VESC gets powered up.
So what do we give up?
We lose the fully isolated opto-isolator input and it’s dedicated connector, as it now is referenced against system ground and added to the CAN-connector, but the enable signal can still be up to +50V level signal.
New connectors would look something like this:
So I’ll let you guys vote based on the information above, which connector setup you would prefer. If you have questions or other ideas those are also welcome.
- Old setup (more flexible connector options at the cost of wiring harness complexity, or slightly increase quiescent current consumption)
- New setup (simpler VESC-compatible wiring harness, lower quiescent current, opto-isolator now ground referenced)
0 voters
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Always cool and interesting updates! Can’t wait to get my hands on one
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In case of the 2nd option:
So what do we actually give up? What does it mean in layman’s therms?
So am I right in thinking the new method would be like the way it was applied in the DieBieMS I mention above
What would this be used for? I’m struggling to think of ways in witch it would be used to work out what the loss would be.
Yes, the implementation for the opto-isolated enable signal input would be the same as in the DieBieMS. Except, as the FlexiBMS doesn’t do discharge path control, it would only wake-up the BMS, but I think it’s still a smart choice to make it compatible (signal wise, not necessary wire order wise) with his BMS.
You could have a completely floating enable signal coming outside, but what that enable signal’s source would be? I’m not sure, but I had put the opto-isolator in from the beginning as it can be a useful feature and it had stayed with that configuration from there, but based on the poll results, which are quite clear which setup people would rather want, I’ll update the layout to the proposed one.
In layman’s terms… I suppose not really anything considering the application environment (esk8, light EVs). It would be needed more with heavier EVs (like in car scale or bigger), where you might be charging your car straight from a 230V AC mains socket from the wall and there is need for some comms in there (some colleagues working on car charger for another customer at the office, so I have some info through osmosis). You might want some true isolation in that use case, but we are almost without exception operating through AC/DC converters with lower voltage output side.
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Sorry @SimosMCmuffin, I read through the whole thread and I am not understanding what the difference with this bms versus a 30euro bestech bms is. The highlighted quotes above is what I understand, the rest I don’t 
Sorry for being naive, just trying to understand 
More compact and a few more tech features is the jist
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How is the link with the metr pro coming along will it be configurable thro the metro app and the information acesablr thro it?
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Bestech is garbage.
I hope this doesn’t get outsourced to chinatown. Will gladly pay the extra $ for build quality. 
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that is what i am hoping! I want to get my hands on one as soon as production is ready 
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