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Discussion Starter #1 (Edited)
As some of you might have been aware there has been some projects out there that have gotten the Tesla BMS slaves to work.

I have participated in a few. Currently I am working on getting software written to do all the basics like:
-Overvoltage monitoring
-Temperature monitoring
-Undervoltage monitoring
-Balancing during charge
-Current measurement
-AH counter

Outputs
-Contactors/relays or other 12V signals
-PWM 'gas/fuel' gauge control
-Serial interface for Victron VE direct, a special request from Boekel.

The BMS controller/master is based around a teensy 3.2 and code is written in arduino. I will look at uploading my files to github so other can have a look and use it as inspiration.


https://www.youtube.com/watch?v=zmT5o5vDoH8

GITHUB

https://github.com/tomdebree/TeslaBMS
 

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I was just at this moment looking at the github for this and logged on here to find the original discussion to learn more about it. I have not looked into a BMS system yet for my tesla batteries so probably have some newb questions.

My current understanding is i wire the BMS boards together and plug them into a arduino due or teensy 3.2. What i'm not sure is what happens from there.
How does the arduino tell the charger/ controller to start or stop.
how do these relate to a precharge resistor?

Thanks for your advice.
 

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Discussion Starter #10
Here is a quick and dirty schematic.

It runs a Uno which reads a pot and changes the pwm duty cycle for the fet driver.

Mosfet is VS-FB190SA10
Used Driver is mcp1407

It will get a tempsensor on the heat sink so it does not overheat during testing.
 

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Good work, Tom. We have been able to source the connectors to attach to the Tesla board to build a wiring harness.

Have you thought about alarming wrt cell differential?
 

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Discussion Starter #15
On the load bank front, I need to add some capacitance on the input which is kind of logical, but i just forgot for some reason. :)

however knocked up two more boards for some beta testers.
 

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Discussion Starter #16
got some more testing done.


Proven out my bms will work and my load is stable so now to increase the power draw for higher current tests.
 

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I have a few Tesla bms from the Rav4 ev (6cell) and at least one from the Smart car ev (15cell).
Is there any interest in taking a crack at those? You know, for science!
There are plenty of those out there as well.
 

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Discussion Starter #18
If you mind posting them over I can take a crack. Or just some good pics of the boards would be a good start.

Or if you are software inclined and have an arduino due or Teensy give it a try yourself.
 

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Discussion Starter #20
RAV4 6s modules should work with the Telsa software/communication that is open source. As it uses the same layout as the Tesla model S.

Smart Car BMS looks different, what does the back side look like? It would be wierd if they would not use the Texas Instruments bms cell.
 
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