search

syssi / esphome-jk-bms

ESPHome component to monitor and control a Jikong Battery Management System (JK-BMS) via UART-TTL or BLE
Apache License 2.0
403 stars 134 forks source link

Total Voltage showing the wronge value #449

Closed RFDarter closed 1 month ago

RFDarter commented 4 months ago

Model: B2A20S20P old-sytle Hardware Version: V11 H.X Software Version: V11.288H Connection Mode: BLE protocol_version: JK02_24S

Total Voltage stays at 0 but the app shows the correct value.

Here is a already structured bt snoop generated by the script tmp_output.log total voltage changing between 1.48V and 2.96V a couple of times

RFDarter commented 4 months ago 
  // 118   4   0x03 0xD0 0x00 0x00    Battery voltage       0.001        V
  float total_voltage = (float) jk_get_32bit(118 + offset) * 0.001f;

150 seems to be correct one.

I only have a new B2A20S20P and B1A8S10P both Hardware Version: V11 H.X

Did 118 work as total voltage on other devices?

RFDarter commented 4 months ago

Offset 32 would fit it, so maybe my devide is 32s after all? I going to look into that tomorrow. If that is the case my frame positions for heating would need to be adjusted to take the offset into account

syssi commented 4 months ago

I will double check the total voltage position on a new and old BMS today but I'm pretty sure it's exposed properly if the correct protocol version is selected.

RFDarter commented 4 months ago

I will double check the total voltage position on a new and old BMS today but I'm pretty sure it's exposed properly if the correct protocol version is selected.

yep, my bad. It turnes out my bms is a 32S and not a 24 as i thought. here is a fix for heating https://github.com/syssi/esphome-jk-bms/pull/457