BMS Communication

On this site I have collected all information about how to connect different BMSes to the Victron Venus OS. This will work with any Victron GX device or the Raspberry Pi running Venus OS.
BMS Communication can be used just for information purposes, so you can monitor your BMS while away from home, or for fully controlling your solar-battery system through your BMS.

RS485-BMS Connection to Victron Venus OS

A very nice gentleman named Louis van der Walt is currently developing a solution for connecting some of the most popular BMSes like JK, JBD, DALY, Heltec to the Victron Venus OS. He’s doing this in his own time and publishes the software for free. So please support him by clicking on his website and donating to him!

Here is my workshop tutorial video where I show how to install Louis’ driver in a beginner friendly way on a Raspberry Pi with Venus OS. We also connect two different JK-BMSes and one Daly at the same time. The same principal will work with all other BMS mentioned on Louis’ website.

I have successfully tested the following USB-RS485 converters and adapters with Louis’ driver:

Waveshare Industrial USB To RS485 Converter with FT232RL Chip
The most expensive adapter in the round but this was confirmed by several people in forums to be working.
I also wanted to test if there is a difference in speed and reliability to the other cheaper adapters.
The adapter comes with a small screwdriver, a removable terminal adapter and 1m USB extension cable in the box. It also has several protection features which other cheaper adapter may not have.
AliExpress product link
Amazon product link

Industrial USB To RS485 422 Converter with CH340G Chip
This is the cheapest adapter I could find online. I wanted to see if it works and … it does. No real difference to the more expensive ones…
AliExpress product link
Amazon product link

RS485 to USB Adapter Converter
Not sure which chip this one has but it works with the driver.
It has a removable terminal adapter and comes with a short 20cm USB cable and a slim USB plug. This makes it really easy to plug into the Raspi directly and don’t block the neighbouring ports. It also has two LEDs to indicate data transfer. Great device, it’s my favourite.
AliExpress product link

Jikong BMS RS485 Adapter
Please pay attention here and confirm with the shop that this adapter will work with your JK-BMS. There are two versions out there:
– for the 4s-8s BMS
– for the 8s-24s BMS
AliExpress product link

You can also just use a USB-TTL adapter and connect Tx, Rx and ground directly to the BMS (no need for this JK-adapter here then). You would need the small JST plug to connect to the BMS though. Not sure if this is actually a JST connector.
AliExpress product link

Daly USB-UART cable
With this cable you can pretty much connect any Daly Smart BMS to the Victron system. There is no further adapter needed.
AliExpress product link

CAN-BMS Connection to Victron Venus OS

Thanks to Kevin Windrem, we now have an easy solution to connect CAN-BMSes to the Victron Venus OS. They show up in the same way as the above BMSes connected through RS485. Almost any smart BMS can therefore act as the battery monitor in Venus OS.
I made a video with a step-by-step procedure on how to connect your CAN-BMS to Venus OS.

Both CAN adapters below are working with Kevin’s software and script. If it does not work right away, just keep rebooting and installing it until it works. I’ve shown the process in the video above.

RS485 CAN BUS Module HAT Expansion Board for Raspberry Pi 
– Operating voltage: 3.3V
– CAN controller: MCP2515
– CAN transceiver: SN65HVD230
– 485 transceiver: SP3485

I’ve got this one installed and it finally works. I don’t know what was wrong, but I rebooted and ran the installer a few times until it eventually started working.

AliExpress product link
Amazon product link

2-Channel CAN BUS Extension Expansion Board Module HAT Kit for Raspberry Pi
I installed this one on my Raspberry Pi and it worked right away. It connected to my Seplos BMS which now shows up in Venus OS as a battery monitor. The adapter is also isolated. Perfect!
The video with step-by-step procedure is just above.

Amazon product link

Running out of USB ports on your Raspberry Pi or Cerbo GX? Don’t want to use these cheap DIY USB adapters wich are not isolated to connect your Victron solar charge controllers?
No problem. down here is exactly what you need to save on SUB ports as well as make your installation way safer by using this 4-port USB converter with isolated ports. Watch the video where I show the details and how to set it up. It’s very easy.

USB – UART Converter with 4 isolated ports
This is an amazing product. It connects up to 4 Victron devices to one USB port of your GX device. It is plug and play and does not need any configuration.
The converter is now available with Pin header or with JST connectors. Great!
Product link and more information

They also have the VE.Direct cables in different lengths in their shop now!

JST 4-Pin Male Header Cable
Unfortunately, I could not find any on Amazon or AliExpress which have these male pins at the end. Most of them have just a bare wire end. You may want to solder them to your USB TTL adaptor.
AliExpress product link
Amazon product link

I think you can order the cables with separate female sockets from here. These are the exact same ones I showed in the video:
Core Electronics

Seplos communication to Victron Venus OS

Here is how to parallel several Seplos batteries/BMSes and connect them to the Victron Venus OS, either on a GX device or on a Raspberry Pi with CAN-Hat as described a bit up on this page here.

The information oonline and the Seplos documentation are not very good, if you want to connect multiple Seplos BMSes to the Victron System.
We’re using RS485 for the internal communication between the batteries as well as CAN communication from the master battery to the Victron System.
This can be very confusing. So, hopefully this video and information clears things up, and helps you connecting your batteries to the Victron OS.

Seplos Google Drive
Seplos RS485 and CAN DIP Switch settings
Seplos Battery Monitor 2.9 (NEW)
Seplos BMS Firmware 2.8 (Dropbox link)
Seplos Android App (for iOS search for EN BMS in the Apple store)

All links on this page are affiliate links to support the channel. I’m getting paid a small commission if you order products or services through these links. This does not make the products or services more expensive for you.

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