JBD BMS with SRNE Inverter.

Been running a JBD BMS on my narrowboat for the better part of two seasons now, paired with an SRNE inverter-charger, and the combination has been... mostly fine, with a few quirks worth discussing.

The main thing I've noticed is the SRNE doesn't always play nicely when the JBD trips on low voltage. The inverter throws a fault rather than gracefully shutting down, and getting it to restart sometimes requires a full power cycle. Not ideal at 11pm on a dark stretch of canal.

I've seen some folk use a Victron SmartShunt in the loop to give better SOC monitoring, which then at least gives you more warning before the BMS actually pulls the plug. That's probably my next addition honestly.

The communication side is where it gets interesting — the JBD has BLE and RS485 outputs, but SRNE uses their own protocol for their battery comms port. Anyone managed to get actual CAN or RS485 chatter working between the two? I've had a dig through the JBD app settings and nothing obvious jumps out.

For what it's worth, my setup is:

• 4S 280Ah LiFePO4 cells with JBD 200A BMS
• SRNE 3000W inverter-charger
• Fogstar cells (which have been rock solid)

Wondering if anyone else has hit the fault-on-BMS-trip issue, or found a workaround beyond just setting conservative voltage cutoffs in the SRNE itself to avoid the JBD ever needing to step in. That's my current bodge and it feels like exactly that — a bodge.

Would love to know what others are doing. Surely someone's cracked this pairing properly?

@KangooAdventure "mostly fine" is doing a lot of heavy lifting there! I ran a JBD BMS briefly on my motorhome before switching to a Daly and then ultimately a Batrium — the JBD's CAN/RS485 comms never played nicely with anything non-Victron in my experience.

Specific question: are you seeing the SRNE drop into absorption too early because it's reading cell voltage rather than pack voltage? That was my exact headache. The BMS was balancing mid-charge and the voltage sag across the cable run was convincing the SRNE that it had already hit the absorption threshold.

Worth checking:

• Sense wire routing directly at the battery terminals
• Absorption voltage set slightly higher (3.55V/cell rather than 3.45V)
• Whether the JBD's overcurrent protection is interfering with the SRNE's bulk phase

What firmware version are you running on the SRNE? That made a noticeable difference for me.

@AndyRobinson curious what you switched to instead

Had JBD on my static van for about 8 months. The SRNE comms never played nicely — ended up just running it dumb with no BMS-to-inverter talk at all. Honestly? Works fine. The JBD handles cell protection, the SRNE does its thing independently.

Main quirk I found was the SRNE's absorption settings being too aggressive for LiFePO4 — had to manually dial it back. Nothing to do with the JBD specifically, just SRNE being a bit obtuse about lithium profiles.

If you want proper integration, Victron + a decent BMS is the only combo I'd trust. But if budget's tight and you're not chasing perfect comms, JBD standalone is workable. Just don't expect the two devices to actually talk to each other reliably.

@KangooAdventure two seasons on a narrowboat and it's only mostly fine — that's practically a glowing review for anything that lives below the waterline.

@KangooAdventure the comms issue is the one that catches most people out. JBD uses its own protocol over UART and SRNE's inverter-charger wants to see a specific charge voltage handshake that simply never arrives — so the SRNE falls back to its own internal profile.

Practical fix that worked on my Ducato build: set the SRNE absorption and float voltages manually to match whatever your JBD cell-level limits are targeting, then treat the BMS as a hard disconnect backstop only rather than expecting active communication. Bit belt-and-braces, but it's stable.

Worth checking whether your JBD firmware revision supports the extended register set — some earlier versions report SOC incorrectly under load, which can cause premature low-voltage disconnects that look like inverter faults.

What cell chemistry are you running? That changes the voltage maths considerably.