Renogy 3500W 48V Solar Inverter Charger

Has anyone here actually got hands-on experience with this unit? I've been eyeing it up for a while now as a potential upgrade to my current setup, but there's very little real-world feedback floating around compared to the Victron Multiplus equivalents.

A few things I'm specifically curious about:

• How does it handle cloudy UK days? Does the MPPT side of things perform well at low irradiance, or does it struggle?
• Build quality — Renogy's panels have been solid in my experience, but I've heard mixed things about their inverter/charger range
• Compatibility with lithium — I'm running Fogstar Drift 100Ah batteries and wondering if the charge profiles are configurable enough to suit them properly
• Noise levels — fan noise is a real consideration for me as the unit would be going in a fairly small space

The price point is obviously attractive compared to going full Victron, but I don't want to end up with something that causes headaches down the line. Is this one of those "you get what you pay for" situations, or is Renogy genuinely closing the gap on the more established brands?

Would also be interested to know what transfer switch times people have experienced — I've got a few sensitive bits of kit that don't play nicely with slow transfers.

Anyone running this long-term (12+ months) who can share thoughts on reliability?

@BoatFinn I ran one of these on my narrowboat for about eight months before switching to a Victron Multiplus-II. Honest take: it's decent for the money, but the documentation is genuinely terrible and the comms options are limited compared to Victron's ecosystem.

A few things worth knowing:

• The transfer switch relay is slow — noticeable clunk when switching to shore power
• Fan noise is considerable under load
• No proper CAN bus integration if you're planning a more sophisticated BMS setup later

The MPPT side performed reasonably well though, and I never had any reliability issues. Just found myself wanting more data visibility and integration options as my setup grew.

If budget is tight it'll do the job. If you think you'll want to expand, factor in the upgrade cost now rather than later — I wish I had.

@DorsetSolar curious what specifically pushed you toward the Multiplus-II — was it the integration with Victron's ecosystem (MPPT, Cerbo, etc.) or actual reliability issues with the Renogy unit itself?

I'm weighing this up for my static caravan setup running Fogstar 48V lithium. My main concern with the Renogy is the BMS comms — does it actually communicate properly with third-party batteries or is it essentially dumb charging profiles only?

Also wondering about the transfer switch speed. Running a few sensitive bits of kit so anything sluggish could be a problem.

@BoatFinn what's your current setup? If you're already on Victron MPPT it might be worth factoring in the monitoring headaches of mixing brands before committing.

@DorsetSolar eight months is actually a decent trial — long enough to see it through a proper UK winter which is the real acid test for any inverter/charger combo.

I've had the Renogy 3500W running in my shepherd's hut since last spring and honestly it's been solid enough, but the lack of proper BMS communication with my Fogstar Drift lithium bank is the thing that'll eventually push me toward Victron territory. You're essentially flying blind on cell-level data.

The charging profiles are configurable but clunky — buried in menus that clearly weren't translated from Mandarin by anyone who's ever actually used a battery.

@WattKaren the Victron ecosystem lock-in is real, but once you're in it, everything talks to everything. That's hard to put a price on when you're trying to diagnose a fault at 11pm in a field.

Had one on my garden office build for about six months. Solid enough unit for the price, but the BMS communication is basic — no proper CAN bus integration if you're running a smart lithium bank (Fogstar Drift, etc.).

The Victron ecosystem (@WattKaren's point is relevant here) wins on that front — DVCC, VE.Bus, the whole lot just talks to each other properly.

Where Renogy makes sense:

• Tight budget
• Simpler AGM/gel setups
• You don't need fancy monitoring

For a boat though @BoatFinn, I'd think carefully. Marine environment is tough on electronics and Victron's support network in the UK is far better if something goes wrong mid-season. Renogy UK support has been hit-and-miss from what I've seen on here.

If budget's tight, look at the MPP Solar units as a middle ground too.

@CE_Builds BMS comms issues — so basically it's the strong silent type, except you actually need it to talk to your batteries before something goes pop at 2am.