SCourt
New Member
Hello all,
I recently bought a JK-BD4A8S4P BMS in order to look after a 4S LiFePO4 battery.
I specifically chose a BMS that had a UART port so that I could monitor the state-of-charge from a RaspberryPi, using either a USB-UART adapter, or by directly connecting the UART port to the RPi (with an appropriate galvanic isolator).
The good news is that I was able to connect my PC to the BMS using the JK-BMS-Monitor software (after setting the UART protocol in the BMS to be #001).
The next challenge was to find some software to run on my RaspberryPi. Here's a list that I've been looking at so far:
When I started looking through the source code I could see that they were sending packets that started with "0x4E 0x57". This lined up with the various JK BMS protocol documents that I've seen, but strangely didn't line up with the protocol that the JK-BMS-Monitor tool was using.
I'm aware that the JK BMS can be configured to use different protocols for the UARTS and I've tried both of the following without any joy:
I'm starting to lose my mind, so I'd be grateful if someone can provide some insight as to how I can monitor the BMS from my RaspberryPi.
My apologies if this question has popped up before in different threads but I wasn't able to find an answer specific to what I was seeing.
I recently bought a JK-BD4A8S4P BMS in order to look after a 4S LiFePO4 battery.
I specifically chose a BMS that had a UART port so that I could monitor the state-of-charge from a RaspberryPi, using either a USB-UART adapter, or by directly connecting the UART port to the RPi (with an appropriate galvanic isolator).
The good news is that I was able to connect my PC to the BMS using the JK-BMS-Monitor software (after setting the UART protocol in the BMS to be #001).
- When I opened the terminal within the JK-BMS-Monitor tool I could see the hex data being transferred between my PC and the BMS.
- The PC appeared to be periodically sending 11 byte packets approx every 1 second
- Each packet from the PC contained the following "0x01 0x10 0x16 0x20 0x00 0x01 0x02 0x00 0x00 0xD6 0xF1".
- The BMS was returning 308 byte packets in response. Refer to the attached screenshot showing the start of each packet being "55 AA EB 90" etc.
The next challenge was to find some software to run on my RaspberryPi. Here's a list that I've been looking at so far:
- https://github.com/jblance/mpp-solar
- https://github.com/syssi/esphome-jk-bms
- https://github.com/sshoecraft/jktool
- https://github.com/ai-republic/bms-to-inverter
When I started looking through the source code I could see that they were sending packets that started with "0x4E 0x57". This lined up with the various JK BMS protocol documents that I've seen, but strangely didn't line up with the protocol that the JK-BMS-Monitor tool was using.
I'm aware that the JK BMS can be configured to use different protocols for the UARTS and I've tried both of the following without any joy:
- Protocol#001 = JK BMS RS485 Modbus V1.0
- Protocol#013 = (9600)JK BMS RS485 Modbus
I'm starting to lose my mind, so I'd be grateful if someone can provide some insight as to how I can monitor the BMS from my RaspberryPi.
My apologies if this question has popped up before in different threads but I wasn't able to find an answer specific to what I was seeing.
