royhen99 wrote: ↑Tue Mar 07, 2023 5:16 am
This came up in another thread a few weeks ago. The hysteresis value is too high and also the battery is almost fully charged. I am not totally sure on this but If you reduce the charge hysteresis to 100mV it might work.
Thanks, Roy. I reduced the hysteresis but then realized all the time I've spent sitting out here with the charger plugged in has led to me being 4.15V lol. So I guess I'll have to drive it to work tomorrow and try again when it actually needs a charge.
Re: Simp BMS
Posted: Tue Mar 07, 2023 12:36 pm
by tom91
vwbrady wrote: ↑Tue Mar 07, 2023 5:36 am
Thanks, Roy. I reduced the hysteresis but then realized all the time I've spent sitting out here with the charger plugged in has led to me being 4.15V lol. So I guess I'll have to drive it to work tomorrow and try again when it actually needs a charge.
So the charger does not listen to the SimpBMS ?!?
Re: Simp BMS
Posted: Wed Mar 08, 2023 4:32 am
by vwbrady
tom91 wrote: ↑Tue Mar 07, 2023 12:36 pm
So the charger does not listen to the SimpBMS ?!?
I've not been able to get the charge enable output to come on until the tip from Roy, so no I guess it doesn't!
BTW I'm using a Chevy Volt charger—the one with the PWM control input.
Re: Simp BMS
Posted: Wed Mar 08, 2023 9:39 am
by tom91
vwbrady wrote: ↑Wed Mar 08, 2023 4:32 am
I've not been able to get the charge enable output to come on until the tip from Roy, so no I guess it doesn't!
BTW I'm using a Chevy Volt charger—the one with the PWM control input.
You are responsible for the design in the end of the day, if the BMS has no way of interacting with the charger and stopping it that is up to you.
I do not know how you are controlling it with PWM, I would highly recommend having something look at the can bus messages from the SimpBMS and set target voltage and current. Once Current goes to Zero switch the charger off and also possibly look at the 12V output for charge enable.
There are alot of ways to integrate it all, there is alot of emphasis on letting the installer define his or her own system setup and take the final responsibility for functionality and safety.
Re: Simp BMS
Posted: Thu Mar 09, 2023 6:08 pm
by vwbrady
tom91 wrote: ↑Wed Mar 08, 2023 9:39 am
You are responsible for the design in the end of the day, if the BMS has no way of interacting with the charger and stopping it that is up to you.
I do not know how you are controlling it with PWM, I would highly recommend having something look at the can bus messages from the SimpBMS and set target voltage and current. Once Current goes to Zero switch the charger off and also possibly look at the 12V output for charge enable.
There are alot of ways to integrate it all, there is alot of emphasis on letting the installer define his or her own system setup and take the final responsibility for functionality and safety.
I am aware and comfortable with the risks I take.
the GM Volt charger is PWM controlled along with a 12v enable, no CAN. There is a PWM status output that tells you voltage but I haven't bothered with that much. The simp BMS is now controlling the 12v enable on the charger.
New challenge is figuring out why the nextion display only updates data when it's power cycled. The SoC doesn't change but the voltages do. So while i'm driving I have to watch voltage to see SoC.
Re: Simp BMS
Posted: Thu Mar 09, 2023 6:32 pm
by tom91
vwbrady wrote: ↑Thu Mar 09, 2023 6:08 pm
New challenge is figuring out why the nextion display only updates data when it's power cycled. The SoC doesn't change but the voltages do. So while i'm driving I have to watch voltage to see SoC.
Okay that is weird as it does get broadcast as you can see the voltage change. Can you confirm which display file and SimpBMS firmware you using?
Re: Simp BMS
Posted: Thu Mar 09, 2023 6:34 pm
by vwbrady
tom91 wrote: ↑Thu Mar 09, 2023 6:32 pm
Okay that is weird as it does get broadcast as you can see the voltage change. Can you confirm which display file and SimpBMS firmware you using?
I purchased the setup through kitoffgrid like 2 years ago and haven't updated any firmware. I'll take a look and maybe record a short video when I get home.
Re: Simp BMS
Posted: Fri Mar 10, 2023 4:31 pm
by vwbrady
it's hard to see in the video, but the display is V1.0.0
video shows the key cycle that updates the SoC meter. The photos are the SoC and voltage prior to trip.
Anyone successfully using the Simp BMS with the 7s Tesla module packs from a B250e or Rav4?
Re: Simp BMS
Posted: Wed Mar 22, 2023 9:56 am
by tom91
robertwa wrote: ↑Tue Mar 21, 2023 10:56 pm
Anyone successfully using the Simp BMS with the 7s Tesla module packs from a B250e or Rav4?
B250e works, I have ran vehicles myself.
Rav4 has different ICs on them.
Re: Simp BMS
Posted: Sat Apr 08, 2023 11:39 am
by Ev8
Will add to my GitHub and link it here later but my implementation of the outlander charger is slightly different (I use the bmw phev bms but the main loop doesn’t differ much) I have added a wakeevse function called by cell voltages < charge set point which just sends the 285id message to wake up the evse meaning 240v is available to a relay to set (IN3) high and change bms status to charge (if other conditions are met) and calls the chargercoms function and send the 286id message to set charge current.
I found this the easiest way to initiate charge, keeping both can messages in the chargercoms function means you need some other way other than ac present to enable charge.
It’s probably not the most elegant solution but it worked for me
Re: Simp BMS
Posted: Sun Apr 09, 2023 1:07 pm
by alexbeatle
Is the isolation monitoring (HV to chassis leakage) a feature that is available with the SimpBMS?
Re: Simp BMS
Posted: Sun Apr 09, 2023 3:17 pm
by tom91
No its not as it requires specific and dedicated hardware. I have provided support of a chinese Isolation monitor and the Bender solution in my new product EVS-BMS. Can add it to the SimpBMS if required.
Re: Simp BMS
Posted: Sun Apr 09, 2023 4:11 pm
by Bigpie
What's the Chinese isolation monitor? The outlander one looks pretty standalone from memory but not sure if anyone's done anything with it. I've got a couple of the GTE boards that can do it, but not tried to figure out how they work.
tom91 wrote: ↑Sun Apr 09, 2023 3:17 pm
No its not as it requires specific and dedicated hardware. I have provided support of a chinese Isolation monitor and the Bender solution in my new product EVS-BMS. Can add it to the SimpBMS if required.
Yes, please do add it to the SimpBMS. At least it will be an option.
Is it hardware or software update?
Re: Simp BMS
Posted: Mon Apr 10, 2023 10:22 am
by Ev8
as promised BMWphev - outlander charger
I haven't forked due to the fact i'd like to keep it separated until someone else confirms they are happy with the implementation, i kinda just copied Jamie's spaceballs code where needed (so we also get charger info in the serial terminal) but like i said above Isplit the can messages apart to use one to wake up the evse before entering charge status.
alexbeatle wrote: ↑Sun Apr 09, 2023 11:05 pm
Yes, please do add it to the SimpBMS. At least it will be an option.
Is it hardware or software update?
You need to purchase hardware to make it work, it is over canbus. I might have one I can sell you, please message me if interested.
Re: Simp BMS
Posted: Wed Apr 12, 2023 6:48 am
by Jacobsmess
Any chance of getting this to work with IPace modules? I'm wanting to break a pack down for a more usable weight/size but I'm not sure how I'd go about controlling the 78S (26 modules) configuration without purchasing an expensive BMS.
Re: Simp BMS
Posted: Wed Apr 12, 2023 8:12 am
by tom91
Jacobsmess wrote: ↑Wed Apr 12, 2023 6:48 am
Any chance of getting this to work with IPace modules? I'm wanting to break a pack down for a more usable weight/size but I'm not sure how I'd go about controlling the 78S (26 modules) configuration without purchasing an expensive BMS.
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.