Growatt inverter + Gospower battery

Been running a Growatt SPF 3000TL on my narrowboat for about 14 months now and it's held up reasonably well, though I did have an early firmware headache getting it to communicate properly with non-Pylontech batteries.

The Gospower units are interesting — decent cell quality from what I've seen in teardowns online, but the BMS integration is where things get murky. Anyone actually confirmed which CAN bus protocol Gospower is using? The Growatt documentation is characteristically vague on supported third-party packs.

My current setup is Victron BMV-712 monitoring a 200Ah Fogstar Drift LiFePO4, so I've not gone the Gospower route myself, but I've been tempted to add a second bank and the pricing is attractive.

A few things I'd want to verify before committing:

• Charge voltage ceiling — some Growatt profiles push to 58.4V which is aggressive for certain BMS configurations
• Low voltage disconnect timing — does the inverter actually respect the BMS cutoff signal or does it race against it?
• Idle draw — the SPF 3000 pulls around 18W at idle which matters overnight on a boat

Has anyone got the Gospower talking natively to the Growatt via the BMS port rather than just running in dumb mode with manually configured parameters? Dumb mode works but you lose the safety net of proper cell-level communication.

Would also be curious whether anyone's tried this combination in a static caravan setup where you've got more predictable load patterns — might actually be a cleaner test case than boat life with its constant variables.

@PN_Camper that firmware saga rings painfully true — spent three evenings on my own boat diagnosing what turned out to be a handshake issue between the inverter and a third-party BMS. Classic narrowboat "why is nothing simple" moment.

Curious what you settled on for the comms fix in the end. I ended up bodging a custom RS485 cable with some specific resistor values after a tip from someone on a CAN bus thread elsewhere — not elegant, but it's been rock solid since.

One thing worth watching with budget inverter/battery combos: the charge voltage tolerances can drift slightly over time. Worth keeping an eye on cell-level balance if your BMS exposes that data. Learned that the hard way before I switched to a Victron setup on my main array.

What BMS are the Gospower units running internally?

@PN_Camper what battery are you running alongside it? I've got a Fogstar Drift 200Ah paired with a Victron MultiPlus on the shepherd's hut and communication was straightforward, but I've heard the Growatt can be picky about BMS handshaking with certain packs.

On narrowboats specifically — are you seeing any issues with the inverter coping with inductive loads? Things like the bilge pump kicking in or a washing machine motor starting up. The 3000TL's surge capacity looks decent on paper but real-world on a boat can be a different story with voltage sag on longer cable runs.

Worth double-checking your cable sizing if you haven't already. A lot of grief on boats traces back to undersized DC cabling rather than the inverter itself.

@PN_Camper narrowboat installs are interesting — the damp environment does funny things to comms cables over time, worth checking your RS485 connections if comms drop again.

@WD40Wizard11 I've got a Gospower 200Ah LiFePO4 on my setup (not on a boat, home backup) paired with a Victron MultiPlus-II and honestly the Gospower has been rock solid. BMS comms took a bit of faffing but once it clicked it's been fine. Fogstar Drift is probably the more popular choice round here but Gospower's build quality seems decent for the price point.

Anyone running Growatt + Gospower specifically? Curious whether the CAN/RS485 handshake plays nicely out of the box or if there's the usual protocol dance to go through — some of the Gospower units seem to support multiple protocols which helps.

@PN_Camper Gospower's BMS comms are about as forthcoming as a wet alternator on a Tuesday — if you're not seeing clean data in the Growatt ShinePhone app, check your RS485 termination resistor first before blaming the battery, because I lost a weekend to that exact nonsense on my boat.