BYD Atto 3 battery contactors controle with stark CMR

[bartremes]

Hi,

Today I went to a car wrecker that have an BYD Atto 3 battery.
When nothing was connected the external volmeter on the HV gave 0V
When I connect the stark CMR The voltage meter on the HV gave 416V !!

I could read out all the battery details like "more battery info" and "cellmonitor"

But when I Click "open contactors" the voltage meter was still giving 416V and I do not hear a clicking sound of contactors that open or close.

I also clicked "unlock crashend BMS" but no difference.

What do I do wrong, or is it not possible to controle the contactors through CAN with a BYD Atto 3 battery?

here some pictures of my setup:

[Ham-120]

Hi Bartremes,
Did you get any resolution on this? I have two batteries and experiencing the same issue on both.

One of the batteries I know was in a crash and airbags had deployed. While I was at wreckers picking them up I had to utilise the CAN replay unlock process to get access to the Battery, ran code, reset everything and then was able to see voltage on the terminals.

Have batteries at home now and I have to connect 12v supply to BMS (Pin4), then Ign (Pin 5), then I power the Battery Emulator from usb battery bank (T-2CAN)(only testing one battery at a time, no inverter setup). When power goes on to the BE the contactors close and voltage can be seen on the terminals.

When I try and open contactors from from BE it goes into fault screen as yours has, doesn't close them. If I then close contactors and go into events and clear events, it goes back to green and healthy state. Only way I seem to get contactors to open is to remove 12v to Ign (Pin 5).

Have tried unlocking bms as you have on both with no success. I cannot get the BE to control the contactors.
I have a Stark CMR on its way..... after 2 weeks without movement from Stockholm Airport, it only just arrived in my country and is now awaiting customs clearance so I may be able to test it by the weekend.

[demon1300]

contactors should now be controllable via CAN

anyone here testted the 10.11 software : BYD Batteries: Added full contactor control via CAN/Webserver (previosly we could only close contactors and never open them) by @demon1300 in #2453 BYD Batteries: Fixed crash that occured when double battery was enabled by @demon1300 in #2427 BYD Batteries: Feature: Extend BYD auto-SOC-calibration and diagnostics to second battery by @demon1300 in #2431

I have... :)

[bartremes]

:)
Thanks for al the hard work!
Do you know if someone is looking into how to get the BMS to work so it will balance the individual cells? Or is that already working? I'm not shure.

[germanfrau]

if someone is looking into how to get the BMS to work so it will balance the individual cells? Or is that already working? I'm not shure.

@demon1300 is trying to work something out for the problem. He needs more lo´gs from cars to get this solved. Maybe you can contribute in some ways.

[Ham-120]

Hi Team,

Thanks for the update and getting this working. BE is working perfectly with full control of both batteries.

I am just balancing the two batteries independently before I join into my system.
I am running two Atto 3 60kWh packs with a 9.99kW Goodwe EHB and everything is working well, I believe on the landing page it notes only the South African EHB is compatible, but I can confirm the AU version has worked without any troubleshooting.

I noticed when starting up the system, the contactors close for both batteries. I had breakers closed on each battery so no issue but an improvement would be to always start with one battery (secondary) having its contactors open.
I know there is information on the wiki which indicates balancing batteries manually first before joining which is what I am doing, I just thought now there is full control over CAN via the BE that the failsafe or starting position should only have one battery with closed contactors to account for anyone potentially having their breakers closed and causing a massive inrush between the batteries.

Anyway, love the project and keep up the fantastic work.

[demon1300]

I'll add this to my to do list to take a look at 👍