Search found 93 matches

by mackoffgrid
Fri Jun 02, 2023 10:12 pm
Forum: Battery Managment (BMS)
Topic: Switched ADC BMS
Replies: 175
Views: 32673

Re: Switched ADC BMS

The gates of the P-FETs are pulled to the voltage they are switching with a 10k pull-up resistor. E.g. gate of FET for V7 is pulled to V7. To turn on the gate is pulled to V0 by its N-FET companion via another resistor, say another 10k. So now current is circulating through two resistors pulling li...
by mackoffgrid
Sat May 27, 2023 2:28 am
Forum: Battery Managment (BMS)
Topic: Switched ADC BMS
Replies: 175
Views: 32673

Re: Switched ADC BMS

And just discovered another issue: grafik.png This is the voltages of my 40Ah ESS pack. When I installed the BMS 7 weeks ago, the delta was 5 mV. Now it is more like 50 mV. I think this is caused by the resistive dividers of the mux being on there 24/7. The lower the cell, the more often will it se...
by mackoffgrid
Wed Jan 25, 2023 2:31 am
Forum: Charging
Topic: DieBieCCS
Replies: 7
Views: 3856

Re: DieBieCCS

dannybokma I think it's great that you (and your client) is making this open source (to the extent you're allowed). This is a technically complex project and I will follow intently. I have no relevant experience in PLC modems or stm32MP1 series of processors, but I will try to follow and question an...
by mackoffgrid
Wed Dec 28, 2022 10:35 pm
Forum: Battery Managment (BMS)
Topic: Switched ADC BMS
Replies: 175
Views: 32673

Re: Switched ADC BMS

When / If the chip shortage comes to an end, the stm32F042 should be the cheapest. If you've stated this before then I apologize :oops:
by mackoffgrid
Tue Sep 06, 2022 1:20 am
Forum: Inverters
Topic: OzInverter Build
Replies: 4
Views: 5597

Re: OzInverter Build

I built my own inverter but something quite different. I have watched the OzInverter evolve since an Aussie engineer diagnosed the heavy standby current in an old Chinese inverter - name I have forgotten; then the modifications of the infamous Power Jack inverter which then led to the "Oz Inver...
by mackoffgrid
Tue Apr 05, 2022 8:48 pm
Forum: Battery Managment (BMS)
Topic: Switched ADC BMS
Replies: 175
Views: 32673

Re: Switched ADC BMS

Finally got my Kicad updated to 6.
Much clearer thankyou.

Having done flying capacitor designs before, well switched capacitor. Thank goodness for JLC, all those little parts add up very quickly :-).

Do you think better than 12 bit res will give you a better SOC calculation?
by mackoffgrid
Fri Apr 01, 2022 10:35 pm
Forum: Battery Managment (BMS)
Topic: Switched ADC BMS
Replies: 175
Views: 32673

Re: Switched ADC BMS

Couple of questions.

Why wouldn't you just use a ADUM1251 to isolate-bridge the I2C to the MCP3421?

I haven't worked through the channel selection logic. Is there a dead-time between channel switching?
by mackoffgrid
Fri Apr 01, 2022 10:00 pm
Forum: Battery Managment (BMS)
Topic: Switched ADC BMS
Replies: 175
Views: 32673

Re: Switched ADC BMS

I've been through a myriad of ideas like this myself. Unfortunately my eyes aren't what they used to be and I find the schematics a bit hard to read. :( but I get the gist and it does have legs. I'd suggest starting smaller, say 12 or 16. There will likely be a practical limit to how many wires you ...
by mackoffgrid
Tue Mar 15, 2022 6:06 am
Forum: Projects
Topic: Solar Powered Ute
Replies: 28
Views: 5761

Re: Solar Powered Ute

Renegate2020 wrote: Sat Mar 12, 2022 9:53 am what wires (color) does dc/dc use?
There is a good thread on the Leaf DCDC converter.
viewtopic.php?f=4&t=1532

If you need more info then let me know and I'll see if I can help
by mackoffgrid
Tue Oct 12, 2021 12:51 pm
Forum: Inverters / Motor Controllers
Topic: STM32 woes
Replies: 54
Views: 12214

Re: STM32 woes

Luckily, most of my electronics was sorted last year, just scraped through with my BMS. The last couple of boards are using old DUE and BLuepill I had lying around. I reckon I'll be going into CPU hibernation after this project.
by mackoffgrid
Tue Oct 12, 2021 12:26 pm
Forum: Projects
Topic: Solar Powered Ute
Replies: 28
Views: 5761

Re: Solar Powered Ute

Getting closer. Fitted the rear battery box. Sits neatly under the tray. A few more gusset plates and we can start loading batteries. The Rear Battery will carry a little over 2/3rd of the total cells. P1000108.jpg The cells will sit in 2 levels. The second level floor will also make this battery &q...
by mackoffgrid
Thu Aug 05, 2021 4:31 am
Forum: Projects
Topic: Solar Powered Ute
Replies: 28
Views: 5761

Re: Solar Powered Ute

:D I am nothing if not slow :lol: The solar Ute project is ticking along .... However I haven't installed the batteries yet. 1/3rd - ish of the cells are going to be fitted in between the radiator and the motor. Construction of the 3 tier aluminium box has taken some time. The rest is going under th...
by mackoffgrid
Thu Jul 01, 2021 10:16 pm
Forum: Inverters / Motor Controllers
Topic: libopeninv STM32F4
Replies: 8
Views: 2469

Re: libopeninv STM32F4

johu wrote: Tue Jun 29, 2021 3:31 pm For a side project I made a branch of libopeninv for the STM32F4.
Might there be some benefit to look at the stm32F3 ? I've never used them but I understand they have a faster PWM clock?
by mackoffgrid
Thu Jul 01, 2021 8:38 pm
Forum: Inverters / Motor Controllers
Topic: libopeninv STM32F4
Replies: 8
Views: 2469

Re: libopeninv STM32F4

Jack Bauer wrote: Thu Jul 01, 2021 5:12 pm It sure looks like the f407 and f107 are pin compatible ....
Yes, one of the strengths of the stm32 families.
by mackoffgrid
Sat Jun 05, 2021 1:22 am
Forum: Battery Managment (BMS)
Topic: Open Source SIMPBMS Board
Replies: 9
Views: 3418

Re: Open Source SIMPBMS Board

For what it's worth, maybe of interest,

I'm likely to use the stm32F413 which has three CAN bus ports for my BMS controller. I haven't studied this processor in depth yet but I'm assuming I can extend my Arduino CAN library to utilise the 3 CAN ports.
https://github.com/mackelec/meCAN
by mackoffgrid
Tue May 11, 2021 9:17 pm
Forum: Nissan
Topic: Nissan Leaf Gen1 DCDC control
Replies: 23
Views: 11514

Re: Nissan Leaf Gen1 DCDC control

I expect you would need to use PWM also to start precharge relays in a proper way? Would someone confirm that? I'm not sure if I understand what you're asking? In the LEAF the DCDC converter or (PDM) is connected to the main high Volt bus so it gets it's pre-charge off the main pre-charge for the w...
by mackoffgrid
Sat May 08, 2021 6:49 am
Forum: General
Topic: Contactors - Best strategy for control?
Replies: 10
Views: 1774

Re: Contactors - Best strategy for control?

In my Solar Ute project, I didn't know where the contactors going to placed so I made a CAN based contactor controller - may seem over the top, but it includes the pre-charge circuit, and detection of full pre-charge circuits . https://github.com/mackelec/CAN-tactorR What is relevant to this discuss...
by mackoffgrid
Sat May 08, 2021 6:16 am
Forum: Inverters / Motor Controllers
Topic: STM32 programming with Arduino
Replies: 10
Views: 2064

Re: STM32 programming with Arduino

stm32F105, stm32L4, stm32F4 Dual CAN Arduino library I've been using exoCan and my own "Bare Metal" code to drive Dual CAN in the stm32F105/107 for a while now. However with the recent chip shortage I've bee forced into upgrading to the stm32L4 controller which meant I had to write a libr...
by mackoffgrid
Fri Apr 16, 2021 6:29 am
Forum: Battery Managment (BMS)
Topic: Open Source SIMPBMS Board
Replies: 9
Views: 3418

Re: Open Source SIMPBMS Board

Great guys, I'll be looking at this closer in a short while
by mackoffgrid
Thu Apr 15, 2021 6:13 am
Forum: Inverters / Motor Controllers
Topic: STM32 woes
Replies: 54
Views: 12214

Re: STM32 woes

JLC have been fantastic - very low cost and even more, convenient for those of us who are prototyping and building for ourselves. While it may be more expensive, it may be better during these times for those like Johannes and Damien who need better supply - Pre-buy the critical parts -( processors) ...
by mackoffgrid
Wed Apr 14, 2021 11:07 pm
Forum: Vehicle Control (VCU)
Topic: The ZombieVerter VCU Project
Replies: 930
Views: 164311

Re: The ZombieVerter VCU Project

I've not used the "G" series before. They look very interesting, but their CAN is FDCAN whereas the "F" series use BXCAN. Multiple 16 bit ADC looks pretty cool. I wonder if it may be too much of a departure from the F series as an early consideration. I of course agree with Damie...
by mackoffgrid
Tue Apr 13, 2021 6:54 pm
Forum: Vehicle Control (VCU)
Topic: The ZombieVerter VCU Project
Replies: 930
Views: 164311

Re: The ZombieVerter VCU Project

That said, for mysterious reasons the STM32F411VET6 is only $3.70 as opposed to $17 for the F107 Prices are all over the place at the moment, It's not just prices, more importantly, it's supply . It's a pity we can't pre-buy parts from JLC to secure stocks. I'm in the process of designing my BMS (a...
by mackoffgrid
Sat Apr 10, 2021 9:52 pm
Forum: Vehicle Control (VCU)
Topic: The ZombieVerter VCU Project
Replies: 930
Views: 164311

Re: The ZombieVerter VCU Project

Yeah BMW fuel gauges don't like filtered pwm to ground :) Ok, I'll go find a digi pot on JLC... A buffered digi-pot is okay but perhaps the problem with filtered pwm is that it's not filtered enough or the pwm is not running at a high enough frequency (for the given Rs and Cs). I made myself a CAN ...
by mackoffgrid
Sat Apr 10, 2021 9:06 pm
Forum: Vehicle Control (VCU)
Topic: The ZombieVerter VCU Project
Replies: 930
Views: 164311

Re: The ZombieVerter VCU Project

I have no issue at all with an F4 device. The problem is (as always for me) the software. At least with the F1 I can get enough of a grip to do the basics while leaning on Johannes and his work. It's essential for me to have that as I do want to be able to do my own mods and modules and at least be...
by mackoffgrid
Sat Apr 10, 2021 6:55 am
Forum: Vehicle Control (VCU)
Topic: The ZombieVerter VCU Project
Replies: 930
Views: 164311

Re: The ZombieVerter VCU Project

EV_Builder wrote: Fri Apr 09, 2021 11:31 pm Why don't we go with the : STM32F4series?

:) With the chip shortages I've been forced into the F4 (and L4) series. :shock: