SA Smart shunt vs dual JBD BMS

[Gurusi]

Hey, through testing and other online posts it seems you have to choose between your BMS/BMS's or a smart shunt to be connected to SA. I wish there was an option to have both devices connected, but im guessing theres a good reason why you cant.

For the past week ive had my smart shunt connected and im happy to look at the SOC accurately. Today i tried hooking up my JBD bms and smart shunt to no avail. So i diconnected the shunt and tried out the bms. I was alittle underwhelmed that individual cells were not displayed (does show highest and lowest).

The reason i bought the shunt was so that i could have an accurate overal SOC between the two 16c packs. Could anyone confirm whether SA will combine the two BMS's SOC to give an overal percentage if I hook them both up?

Is there a consensus on whether its better to go with the BMS or the shunt?

Thanks

 

[timselectric]

Could anyone confirm whether SA will combine the two BMS's SOC to give an overal percentage if I hook them both up?

You can only connect to one or the other.
I'm actually running separate Solar Assistants to monitor both. We have been asking for this functionality. But it hasn't happened yet, sadly.

Is there a consensus on whether its better to go with the BMS or the shunt?

The shunt is more accurate.

 

[42OhmsPA]

SOC and capacity is summed for all packs connected.

 

[timselectric]

What I don't know is whether or not there is a limit to how many devices can be connected.
I'm hoping that 14, or 21, can be.

 

[42OhmsPA]

What I don't know is whether or not there is a limit to how many devices can be connected.
I'm hoping that 14, or 21, can be.

Me too. I do know it recognized a 4 port usb hub with 3 packs connected to it with no issues. In theory you should be able to keep connecting usb hubs and battery packs...

 

[Gurusi]

Me too. I do know it recognized a 4 port usb hub with 3 packs connected to it with no issues. In theory you should be able to keep connecting usb hubs and battery packs...

I bought a waveshare external powered usb hub thinking I would have my inverter, shunt and X2 bms hooked up. Now im wondering if i will need it as i may only have my inverter and shunt connected.

Im new to SA, are firmware updates vast in changes or more bug fixes and new inverter compatibility added? Just weighing up whether options of mulitple devices may open up soon.

 

[42OhmsPA]

I bought a waveshare external powered usb hub thinking I would have my inverter, shunt and X2 bms hooked up. Now im wondering if i will need it as i may only have my inverter and shunt connected.

Im new to SA, are firmware updates vast in changes or more bug fixes and new inverter compatibility added? Just weighing up whether options of mulitple devices may open up soon.

I'm not sure... I hadn't updated it in almost a year because everything just worked then I upgraded my inverter and joined the beta so I've been updating more frequently. It does seem like there are lots of changes across the board with each beta update. I also really hope they add individual cell data so I don't have to swap usb cables to the pc when I want to see pack details.

If you're not aware they have a fairly detailed changelog for each update.

SolarAssistant changelog

Changes introduced with each SolarAssistant release.

solar-assistant.io

 

[timselectric]

Me too. I do know it recognized a 4 port usb hub with 3 packs connected to it with no issues. In theory you should be able to keep connecting usb hubs and battery packs...

Right, hubs are not a problem. I'm using several.
I just don't know if there is a limit to connected devices. That it will display.

 

[Brett V]

I originally connected the Overkill BMS with a Uart adapter but found the available data on SA too limited plus there was no way to change any BMS settings. I now use the smart shunt for SOC and connect to the BMS with bluetooth. Not the cleanest solution but it's the best I can do.

 

[webbbn]

I don't know about JDB BMS, but I have two JK BMS connected to Home Assistant using one $5 ESP32 D1-Mini32 via BLE. (Instructions here). No wires to worry about, and supports almost all the functionality of the app. Just plug it into power somewhere in the vicinity of the batteries and it works.

Looks like there is support for JDB BMS as well here.

 

[Gurusi]

I originally connected the Overkill BMS with a Uart adapter but found the available data on SA too limited plus there was no way to change any BMS settings. I now use the smart shunt for SOC and connect to the BMS with bluetooth. Not the cleanest solution but it's the best I can do.

This is what i have been doing and may be my route going forward, means i can monitor remotely in terms of charge and SOC via the shunt; then bluetooth when at home. its seems the BMS connection gives nothing addtional right now for me.

 

[Gurusi]

I don't know about JDB BMS, but I have two JK BMS connected to Home Assistant using one $5 ESP32 D1-Mini32 via BLE. (Instructions here). No wires to worry about, and supports almost all the functionality of the app. Just plug it into power somewhere in the vicinity of the batteries and it works.

Looks like there is support for JDB BMS as well here.

Thanks for the info, i may look into it when things are fine tuned. So you have an addtional Pii device and OS for Home Assistant and run it alongside SA?

I have Emporia energy setup on my main panel which is cloud based/closed but can be flashed to work with Home Assistant so could be worth it.

 

[timselectric]

For individual cell voltages. I would be happy with highest, lowest, and delta. I can live without lowest, and definitely have no use for average.

 

[webbbn]

Thanks for the info, i may look into it when things are fine tuned. So you have an addtional Pii device and OS for Home Assistant and run it alongside SA?

I have Emporia energy setup on my main panel which is cloud based/closed but can be flashed to work with Home Assistant so could be worth it.

I run HA in a docker container on a Synology NAS, and I don't run SA. I have two ESP32s (one for BMSs and one for inverter) that feed everything to HA via wifi. I could run it all on one ESP32, but it wont quite fit in flash without some more fiddling that I haven't gotten around to yet.

 

[Gurusi]

I run HA in a docker container on a Synology NAS, and I don't run SA. I have two ESP32s (one for BMSs and one for inverter) that feed everything to HA via wifi. I could run it all on one ESP32, but it wont quite fit in flash without some more fiddling that I haven't gotten around to yet.

Ok looks even better. I have a Qnap that can run a docker container. I will look into ESP32s programming and whether there is specific info for my BMS.

 

[webbbn]

Ok looks even better. I have a Qnap that can run a docker container. I will look into ESP32s programming and whether there is specific info for my BMS.

One of the downsides of using HA in docker is that it can't (normally) access USB devices, so initially flashing an ESP32 can be more difficult. Fortunately it's still very easy using ESPHome Online.

 

[Brett V]

This is what i have been doing and may be my route going forward, means i can monitor remotely in terms of charge and SOC via the shunt; then bluetooth when at home. its seems the BMS connection gives nothing addtional right now for me.

SA covers the important stuff. I occasionally look at the cell data on the Bluetooth app but if things are set up and running properly, its not something I need to monitor closely. I only charge to 3.5 per cell and rarely see a delta above .005