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Definitely a nice bit of validation of a used pack. I've seen folks wire up a cheap bluetooth obd adapter to the pack and use android leaf spy too.

Took me a while to figure out your dev board is a rtmcs2 of your own making :)

What is the lowest voltage you think the bms will run on is? (10v for sure, possibly 5v?)
 

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Discussion Starter #3
Finished version, all packaged now:
packSnifferFinal.JPG

Video:
https://youtu.be/e6CroYIOoas

There was one firmware bug in the previous version (shows up in the part 2 video at 3:03), [DrSegatron] noticed that the average cell voltage was higher than the highest cell…

The first pass I sum all the cells and divide by 96.
But each pass after that I never cleared that value from the sum.
So the next pass started with the last average value then summed in the 96 cells, then divided by 96. This caused the average cell voltage to creep up with each pass (97/96).

It is fixed now. :)

Thanks again to [DrSegatron]. :D
 

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Discussion Starter #4
Definitely a nice bit of validation of a used pack. I've seen folks wire up a cheap bluetooth obd adapter to the pack and use android leaf spy too.

Took me a while to figure out your dev board is a rtmcs2 of your own making :)

What is the lowest voltage you think the bms will run on is? (10v for sure, possibly 5v?)
Leaf Spy will work, but ironically you also need a way to power the battery.
Salvage yards tend to get suspicious if you are carrying around a 12V car battery. ;)

Yeah, the RTMCS2 is actually an 8 channel servo controller, but it has become my go to dev board.
I packed a lot of functions into it. Here is its page:
http://www.wolftronix.com/rtmcs2/index.html

It won't run at 5V that was the first thing I tried, and was the reason why I built the 5V to 12V boost converter.

Typical automotive voltage range is 8V to 17V, so I would assume it has to be more than 8V. But I have not tested this.

There is a 5V linear regulator, and a separate voltage supervisor microcontroller reset chip.
 

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Alternatively, if You already have leaf spy pro and elm327 adaptor combo, You can do the same.
 

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Will an elm 327 read data direct from the bms though? As in, with a battery outside the car with appropriate harness and power supply?

Sent from my SM-N9005 using Tapatalk
of course You'll need a round connector for the battery pack and a power supply (12V) to wake up bms cpu and elm, there is identical data over a can line, so it is not important where You will sniff (at obd connector or anywhere else)

BMS is almost standalone unit, it's balancing chips are powered directly from HV pack (from the first cells) and cpu is only gathering info about shunts, cells connections, under/over voltage, esr, and HV isolation phase shift, so it will definately work with or without a VCM connected from the car.
 

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Discussion Starter #10
Hi Wolftronix.

I'm interested in this. Are you able to supply to the UK?

Sent from my SM-N9005 using Tapatalk
Sure...

But I have not been able to source the round connector (22 pin on the 2012 and earlier, and 36 pin on the 2013 and later) for the battery pack...

So I have been thinking about making a few without the connector for those that want them... But I am not sure how useful they are unless you already have the connectors.

You would have to plug in wires like this:
 

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3d Print it. And glue in the "normal" single row 0.1" female headers.

Must be the easiest option
If somebody can supply the cad i'm happy to run off a few on the 3d printer...

Sent from my SM-N9005 using Tapatalk
 

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Discussion Starter #13
3d Print it. And glue in the "normal" single row 0.1" female headers.

Must be the easiest option
I don't have a 3d printer...
But, I like that Idea...

I wonder how hard it would be to make a 3D model...
Would just need to be a cylinder with a two notches in it, and cutouts for the 4 female headers... :)

Thanks,
Wolf
 

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lucky the notches are parallel with the pin rows. So measure that puppy up, sure someone can make a quick model. Else I could make one, but the you need to measure in metric :D
 

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Discussion Starter #15
lucky the notches are parallel with the pin rows. So measure that puppy up, sure someone can make a quick model. Else I could make one, but the you need to measure in metric :D
We use Solid Works here, at work, and I think I can get one of the mechanical guys to model it.

I will bring in the connector and female mates tomorrow and see what happens. ;)

We have a FAB LAB over at the University that lets you 3D print and pay by the hour/material you use. So I think this is a really good solution to a hard to get connector. :D

Thanks,
Wolf
 

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Plus it will be the cheapest. And it is only for testing purposes so need for all the features, just a simple holder for the actual connectors and no weatherproofing or locking.
 

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Discussion Starter #17
Plus it will be the cheapest. And it is only for testing purposes so need for all the features, just a simple holder for the actual connectors and no weatherproofing or locking.
Yeah, it is the perfect application for a 3d Printer. :)
 

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Discussion Starter #20
Gen 1 or gen 2? Have one of each here. If you can make the file available i'll prknt one out here too.

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I wanted to print it first, might need to tweak the centering and the openings for the connectors, before posting it...

But if you wan to try it out and give me feedback on it, I can make adjustments to it while I am still at work. ;)
 
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