Read data from a JK BMS through RS-485 and graph it in Grafana. This script is intended to be used with: https://github.com/BarkinSpider/SolarShed/
The JK BMS can be found on AliExpress and other sites, for example: https://s.click.aliexpress.com/e/_DBEzZwv
Alternatively, a set-up for this is documented here for both Raspberry Pi and plain Debian or derivatives: https://diysolarforum.com/ewr-carta/data_communication/
The JK BMS has an RS-485 port, but this is actually a TTL UART that gets turned into RS-485 with an optional converter, which in turn can be used with a RS-485 to USB converter. While this works, you don't need this whole chain. You can directly connect a TTL to USB converter to the TTL UART port. The pin-out on the connector:
RS485-TTL plug on BMS (4 Pins, JST 1.25mm pinch)
┌─── ─────── ────┐
│ │
│ O O O O │
│GND RX TX VBAT│
└────────────────┘
See this post on DIY Solar Forum for the locaton of this port on various versions of the BMS: https://diysolarforum.com/threads/victron-venusos-driver-for-serial-connected-bms-llt-jbd-daly-smart-ant-jkbms-heltec-renogy.17847/post-424921