JDB BMS

The JDB BMS type is for JBD/Jiabaida battery management systems — the family used inside many DIY and off-the-shelf lithium batteries, managed by the "xiaoxiang" phone app. Installing one adds three dashboard cards:

• Battery — state of charge, voltage, and current.
• Cells — every cell voltage (up to 8), with the lowest and highest highlighted and a Delta pill showing the spread between them in mV (green under 50 mV, amber under 100 mV, red above — a large delta means the cells are drifting out of balance).
• Temps — the two temperature sensors, plus the MOSFET control bar.

The MOSFET bar (BMS On / Off)

The bar on the Temps card switches the BMS's charge and discharge MOSFETs together, and its label shows the combined state: BMS On, Charge Only, Discharge Only, or BMS Off. BMS Off disconnects the battery — everything powered from it goes dark, so treat it like a main switch. The buttons do nothing until the first status has arrived from the BMS (a few seconds after connecting).

Adding one

BMS units advertising as "JBD-…" are recognised in Discovered nearby; others need a manual add with their MAC address (Add device → JDB BMS, then Scan). No key needed. It uses a Bluetooth connection (connection limit), and the xiaoxiang app can't be connected at the same time.

Problems?

• Card frozen → close the phone app, then see A device stopped updating.
• Errors reported by the BMS (over-current, under-voltage…) show on the card; they clear from the BMS side once the condition passes.