Mike Dorsett avatar image
Mike Dorsett posted

Modbus connection of BMS to Venus Gx Device

Due to the difficulty in obtaining Raspberry Pi's and the problems encountered with accessing the spi port from Venus running on a Beaglebone Black, I thought to connect my BMS to a Venus GX device by Modbus TCP/IP: this has now reached the basic functionality stage. I'm currently working on some of the detail settings, but wondering if any one else is interested in this concept.

Working on my original spi battery connection using @Louis van der Walt 's serial battery software, I'm currently updating this to run a Modbus TCP/IP client to D-bus service, so as the GX device thinks it is connected to the BMS.

the test installation is visible here:





So far so good. As mentioned above, this is a work in progress. However, the basic concept will allow a TCP connection to any modbus client - BMS, meter, generator etc.

I seem to recall that last time I tried to get the min/max Cell temperature id's filled in this was not successful, I'm glad to see this bug has been fixed.

What's next?

After getting the remaining data fields connected, I'll probably add the modbus data for the MPPT and the inverter, as an alternative to connecting these directly to the GX.

One possible application for this would be a remote display with full functionality in reading data, but at the moment with no reverse channel for control. This would allow remote data displays elsewhere on a local network.

1696458396738.png (25.3 KiB)
1696458432271.png (23.3 KiB)
1696458462545.png (27.6 KiB)
1696458492497.png (31.4 KiB)
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.



MikeD contributed to this article