Simp BMS

[Jacobsmess]

I have not had the chance of working with the Ipace slaves, so cannot tell you how much effort this would be.

Where are you based? I could look at adding the functionality into the EVS-BMS and open sourcing the info in the SimpBMS format. I currently do not have any SimpBMS due to the missing Teensy 3.2s.

That would be amazing, In based in Leeds UK.

[mitera]

Teensy 4.0 is not the same pinout as the 3.2 so would not work with the SimpBMS board ( without modification ). I have modified the code to run on 4.0, but probably not any use to you using SimpBMS board.

Hi, can you please provide me this modified code? I will try to make reduction on pinout from 4 to 3.2 to make it work. My old 3.2 is burnt and I am try to use 4.0. thx

[royhen99]

I have only tested the VW version on GTE battery, and it may not be fully up to date but here is a link to github. https://github.com/royh99/VW-bms/tree/master/VWBMSV2_T4

[vwbrady]

Please update the BSM firmware according the instructions in the end of the user manual: https://github.com/Tom-evnut/SimpBMS/bl ... 0V0.29.pdf

Alot has been updated since the firmware version 28818

followed the firmware update process and display still does not update unless power cycled.

Has anyone else had this issue?

[alexbeatle]

Any suggestion on how to handle CANbus current sensor (ISA 500kbps) and charger/DCDC (Elcon 250kbps) that run on different speeds? As I understood, these are normally placed on the same CANbus to be controller by the SimpBMS.

[royhen99]

It's fairly simple to set the IVT-S to use 250 kb. Not tried it but I have reset to default and initialised several times to test the initialisation code.
Could be done with SavvyCan, just two messages to ID 0x411.

[alexbeatle]

It's fairly simple to set the IVT-S to use 250 kb. Not tried it but I have reset to default and initialised several times to test the initialisation code.
Could be done with SavvyCan, just two messages to ID 0x411.

I'll have Tesla SDU and likely some version of ZombieVerter VCU to interface with LIM on the same CAN bus.
Edit. I think I'm gonna design a small I/O to CAN board...

[m.art.y]

Figured out the missing temperature feedback value on the canbus.

Hi, I have a question about reading temps on the Tesla BMS slave boards. Is it possible to configure them in software to accept a different type of temp sensor or at least to calibrate them? I have a bunch of temp sensors that came with my battery but when I connected one to the Tesla slave board average temp was shown as around -3 to -6°C while in reality there was +20°C. I don't even know which type of temp sensors I have.

[tom91]

Hi, I have a question about reading temps on the Tesla BMS slave boards. Is it possible to configure them in software to accept a different type of temp sensor or at least to calibrate them? I have a bunch of temp sensors that came with my battery but when I connected one to the Tesla slave board average temp was shown as around -3 to -6°C while in reality there was +20°C. I don't even know which type of temp sensors I have.

Tesla temp sensors are hardcoded. You would need to modify the firmware, there is a simple Steinhart formula to work out the Tesla temps.

Luckily data is sent as an ADC value and not a temperature from the slaves.

[fredsbus]

Current configuration

Five Tesla modules wired in parallel for a 24V pack.
SimpBMS driving two Tesla contactors (+ and -), pre-charge relay with power resister.
CAB300 current sensor
Victron equipment CXCC and three SmartSolar charge controllers.
Ten LG375N2W-G4 panels mostly flat mounted on the top of my forty foot bus/motorhome/caravan for a 3.75KW array.
CXCC is configured for DVCC - Distributed Voltage and Current Control
Off Brand 6KW inverter (Signiteer).

Todays problem:

1. Pack started the day at 55%
2. Solar charging reached 3KW. Not bad for flat mounted on a vehicle and pointed roughly north.
3. Around 85% still had lots of sun, but charge rate was reduced to 700 watts. (Sort of expected).
4. Turned on inverter and killed shore power.
5. Power transfer switch transferred the AC loads to the inverter.
6. Started drawing about 3KW of DC power from the pack.
7. Solar power charge rate was climbing and reached about 1500 watts.
8. An ESS #3 message would appear on the CXCC which means BMS disabled charging
9. Charge rate went to zero and slowly climbed up to around 1KW until another ESS #3 message appeared.
10. This process would continue to cycle.

Suggestions?

Thanks

[bigmotherwhale]

I tried to flash with the updated file today, but when i booted the CMU modules were missing.
I dont think im flashing it correctly, Im using Teensy (the program) and using the hex file from GitHub, i press the button on the teensy then and click upload and everything looks good, but it fails as above.
I remember having this issue before and having to build it with Arduino from the .ino files and then it worked.
Can anyone tell me what i am doing wrong not to be able to flash with the .hex file?
Thanks

[tom91]

I tried to flash with the updated file today, but when i booted the CMU modules were missing.

I did the same just now on the bench, Github .hex for the outlander and a arduino Uno spitting out the outlander canbus and it just works.

[tom91]

Pushed two updates to resolve some issues caused by saving the SOC to eeprom. This means that when a plausible SOC is read it no longer ran a delayed event.

Please update to the latest Firmware if you have any known issues.

[fredsbus]

Update on my ESS #3 message problem where the charging rate would crash.

Turns on there was corroded battery connections between the solar charge controllers and the wiring into the actual pack.

As it would attempt to drive power into the pack there was a large mismatch between the reported BMS pack voltage and what the solar charge controllers were seeing.

Problems went away after cleaning this up.

[m.art.y]

You would need to modify the firmware

Hi, Tom. A question on modifying the firmware. My inverter doesn't control the contactors but it sends a CAN message requesting to close the contactors so I have a separate Due board with some code that responds to the CAN message from inverter via interrupt and closes the contactors. Due also sends a list of CAN messages to keep the inverter happy. I do plan to use Simp V2.4 with Tesla slaves for my battery so would it be a good idea to include my code into the Simp Tesla code to get rid of the Due? Won't it affect the operation of Simp battery monitoring? Some changes will have to be made to Simp code to not close the contactors on 12v signal but respond to CAN message instead and perhaps another change to not drop the contactors on cell failure immediatelly but to send a warning or a fault code first. Doable?

[tom91]

Doable?

You can change anything you want. It just means you are no longer running the standard firmware.

• It already sends warnings and alarms in the Victron CAN bus format.

• In ESSmode there is already a can contactor request I believe, or atleast a selectable enable method.

This means if you make it as a option for the CAN bus profile and for the enable method you should be able to merge these changes into the original coding. Which inverter are you using?

[alexbeatle]

Quick question.
Which option should I select for the SimpBMS to control (ex. tell it to start/stop charging) Elcon charger via CAN bus?
Snapshot from ‘e’ Charging Settings:

Here it says TCCharger/Elcon are supported via CANbus...

[tom91]

Manual is out of date for some parameters. There is the option for the Elcon / TC Charger available.

Charger Type 4 is what you want to set it to.

[alexbeatle]

Manual is out of date for some parameters. There is the option for the Elcon / TC Charger available.

Charger Type 4 is what you want to set it to.

To confirm. Once this option is selected the BMS will talk to charger via CANbus, and will not be controlling this contactor anymore? Or there's a way to enable both, so that the contactor can be used for drive disable.

[tom91]

Contactor/relay is always used. Can Bus is additional.

[amsmntparks]

I saw a V2 version of the Volt BMS and mistakenly thought it was for the Gen2 Volt batteries. Is there any chance someone is working on that?
Regardless, when I loaded that hex on a 2.3 board it gets stuck in a reboot loop. Is that normal if it's not connected to a gen1 CAN?

[amsmntparks]

I spent all weekend trying to get the BMS to work with the Gen 2 pack, and I learned a lot. The biggest takeaways are that the Gen 2 pack uses different CAN addresses and formats than the Gen 1. I'm pretty sure I can get the Simp BMS to work with the new messages based on the DBC info I found on the opendbc github. That would be super cool because I'd be able to interface with the full functionality of the simp BMS and the stock battery board, and it would all work without needing to splice into the stock harness at all.
Unfortunately, this leads me to the second thing I learned this weekend. There's a bunch of warnings in the service manual that say you can permanently screw up the BECM (battery energy control module) by un/plugging in the different battery modules willy nilly. I'm pretty sure that's what I did because I'm not getting any voltages from module 4 (other modules are fine, and module 4 is wired in correctly and measures good voltages).
Anyone know where I can get my hands on another BECM from a gen 2 volt?

[alexbeatle]

A little sanity check please.
Is this a correct way to go for, when Tesla drive (SDU) controls the main contactors - SDU-POSitive and SDU-PREcharge for both drive/discharging and charging. SimpBMS interlocks the SDU via the Start, F-R-N signals? SimpBMS will communicate with the charger via CAN.

Is there a minimum switching time between J5:1 (key on) and J5:6 (charge enable)? Planning to use a 3-position switch for now. Assuming that when the car is charging, putting the switch into Idle possition will make BMS tell the charger to stop charging.

Sorry if my questions are much too obvious...

Thanks in advance

[P.S.Mangelsdorf]

I spent all weekend trying to get the BMS to work with the Gen 2 pack, and I learned a lot. The biggest takeaways are that the Gen 2 pack uses different CAN addresses and formats than the Gen 1. I'm pretty sure I can get the Simp BMS to work with the new messages based on the DBC info I found on the opendbc github. That would be super cool because I'd be able to interface with the full functionality of the simp BMS and the stock battery board, and it would all work without needing to splice into the stock harness at all.
Unfortunately, this leads me to the second thing I learned this weekend. There's a bunch of warnings in the service manual that say you can permanently screw up the BECM (battery energy control module) by un/plugging in the different battery modules willy nilly. I'm pretty sure that's what I did because I'm not getting any voltages from module 4 (other modules are fine, and module 4 is wired in correctly and measures good voltages).
Anyone know where I can get my hands on another BECM from a gen 2 volt?

There is an old thread (that I just woke up) about the Gen2 BMS.
viewtopic.php?p=60737#p60737

It'd be great if there is a simple way to get the Gen2 Volt BMS up and running - it seems like a much better set up than the Gen1.

[tom91]

Is this a correct way to go for, when Tesla drive (SDU) controls the main contactors - SDU-POSitive and SDU-PREcharge for both drive/discharging and charging. SimpBMS interlocks the SDU via the Start, F-R-N signals? SimpBMS will communicate with the charger via CAN.

The diagram is fine, it will disable the SDU from working due to no gear signals, just make sure you set the signals to switch (12V) and not button (momentary 12V)

Is there a minimum switching time between J5:1 (key on) and J5:6 (charge enable)? Planning to use a 3-position switch for now. Assuming that when the car is charging, putting the switch into Idle possition will make BMS tell the charger to stop charging.

It is fine to use a switch to change between them. It checks the inputs continuously.