use Batter Monitor + Virtual Com port to access bms via esp32

[Pho3niX90]

Has anyone succeeded yet with creating a virtual com port using software such as NBVirtualCommPort, and connecting remotely to the bms? Could this even be implemented into the current solution?

[syssi]

You are looking for a solution to forward serial traffic over the network. Please try this external component instead:

https://github.com/oxan/esphome-stream-server

I've used the component here to make the serial line of a zigbee radio accessible via network:

https://github.com/syssi/esphome-zb-gw03/blob/main/packages/core.yaml

[Pho3niX90]

So it seems there needs to be 2 hardware uart's? 2 x RJ45 to 2 x TTL's, connected to different pins on the esp32?

Luckily I do have extra hardware, but hoped a single defined uart would do the trick, as both the "seplos_bms" and "stream"server" would share the connection. But I guess, there would be comms clashing.

[syssi]

You do the following experiment:

1. Try to enumerate the Seplos devices properly (BMS1: 0x01, BMS2: 0x02). Both devices must act as "slave" because your windows application should collect the frames as master.
2. Connect a workstation using a single RS232 port with RS485 converter attached.
3. Try to use the Battery Monitor Application and cycle between the device addresses 0x01 and 0x02.

Does this work? If it's working you should be able to use the same wiring with the ESP32 stream server setup. If you have trouble to talk/address both devices using the same bus you should stick to two different hardware UARTs / two serial lines.

[Pho3niX90]

So I did at first try single hardware, multiple uart's, however, there were interference as both points of data acted erratically.

I setup the second set of hardware, and experienced the same issue. At this stage, I thought the single power brick might be underpowered, and added a second power source. Still the same.

Once the windows app connects, everything acts erratically.
I used the RS485 ports only, CAN is connected to inverter

Each works fine on their own, when the other is switched off. But when both are switched on, things go sideways

Are the dip switches to enumerate your point 1?

I only have 1 pack, so all dip switched are off. address 0x00

[syssi]

Are the dip switches to enumerate your point 1?

Yes.

I only have 1 pack, so all dip switched are off. address 0x00

I'm confused now. How many Seplos BMS to do want to communicate with? 1 BMS per Pack? Two packs in total? :-)

[Pho3niX90]

I only have 1 seplos bms, and 1 pack.

The idea was to use this repo, to integrate into HA, which works great.
The second idea was to have a connection from my desktop, to the seplos, to change parameters etc, since my windows laptop went pop.