Pugeot E-208, Corsa E, etc. battery pack.

[manny]

Digging through the electronics modules from the battery, I found the precharge circuit. I found it interesting because it uses PTC thermistors.

The PTC's are C1412by TDK rated for 620V and 120ohm. The relay is V23700-C0001-A408 made by TE Connectivity 450V and 20A.

The PTC's are arranged in 2S7P making it a 34.3 ohm precharge resistor.

If there is a short on the HV when precharging the PTC's will dissipate 4700W @400V 11.7A. This will heat up the PTC's real quick, and that will lower the current. A normal resistor will not survive for long in this situation.

[tom91]

EDIT: turned out with the closing loop I used I put red to white and black to black. Without realising when I wired it I assumed all TxN and RxN would be on same row but the flip TxN to second row. So with that fixed and wiring check I get 0x21 response

I am really struggling to get this functioning on the bench. Can someone please give me some insight into how to "terminate" the bus with these modules?

I have the M3/MAX BMS from Damien, https://github.com/damienmaguire/Tesla- ... M32_M3_Bms

I am spitting out the SPI as per data sheet and doing the UART chain init, however no RX Status 0x21 is recieved I keep just getting 0x11.

I have made sure SPI works by requesting other register info.

Could someone scope a working RX and TX pair for me to check if the signal is shaped properly.

I can even see the signal going into the module coming out. So in on pins 1+7 and out is 6+12.

[tom91]

Got it now to initialize the string and read out the single module voltages and temp registers.

Currently have a slight issue with the temp register so will dig through others example code to find what I am doing wrong.

Likely due to this:

Now onto the cell temperature sensors. each module has three NTC and are not contacted as the MAX chip manufacturer recommends.

This thread is a goldmine of information.

Edit: I am using the Hyndai/KAI Arduino base code to port from.

Anyone written code to read the PSA modules? Otherwise I will write the code to do it and publish it to Damiens github once i got all read outs working.

[tom91]

Riddle me this, sometimes when starting the STM32 and initializing then reading the E208 module (single for now) the Watchdog kicks the STM32.

So done some SPI digging and the response from the slave module has Data-check byte set to 0x40 better known as PEC error.

However sometimes I switch on the STM32 and let it do its things and it does not cause the slave module to throw a PEC error.

My fix, ignore the error and continue on But have a counter to see if the error occurs. It will happen continuously on one power cycle and not others. Very strange. Need to dive deeper on this one.

[tom91]

Finally gotten 2 modules to work.

Had to rewrite a whole bunch of waiting on the RX register status. Will look at handling this more cleanly. This caused a bunch of issues, likely combination of porting, timing and compiler struggles.

However we now have a dynamic module amount coded in and it seems to work.

[tom91]

Have now gotten the dynamic amount of modules working and introduced the statistics. So much easier to code the "high level" things and not have to debug low level SPI data streams.

Will look to clean up the SPI data routines at a later date.

If you want to follow along or have a M3 MAX BMS board the code is here: https://github.com/damienmaguire/Tesla-M3-Bms-Software

[rstevens81]

Do you want me to point out tempmin is higher than tempmax on your screen shots ... Not that it really makes any difference whatsoever to use general useability

[arber333]

Is there any wiki record of PSA modules dimensions.

[manny]

Yes

https://openinverter.org/wiki/Batteries

In the tabel there are dimensions