Hello Bluetti community. I am setting up 2 x AC300’s (split-phase) and 4 x B300’s in a 1000 sqft cabin. The cabin is grid connected but the area tends to lose power more often than I’m comfortable with. The AC300’s will be fed by ~5kw of solar panels, maxing out the 4 PV inputs and 200w panels per B300. Hoping that will be enough coverage for mid-atlantic sun and seasons.
My goal is to rely on grid only when I absolutely have to, with the majority of the circuits covered by the split-phase setup. Critical: most of the lighting, IoT devices, fridge, well pump (240v, 20A), hot water heater (240v, 30A), and possibly the mini-splits (240v, 30A). Minimal use, but at least some coverage as needed. The range, dishwasher, and washer/dryer are out (for now). But capacity sizing is secondary to what my main issue is…
With all that laid out, I can’t tell you how many hours I’ve spent on here, other forums, Google and YouTube trying to determine how to best lay this all out . My initial plan – which seemed like the obvious approach – was to use the Pro/Tran2 transfer switch for all the critical circuits, switched to the AC300’s full-time, so PV/battery is my primary power source with the option to switch to grid if needed. But after reading all of the nightmare stories of Bluetti customers who doubled as guinea pigs and beta testers and blowing several units along the way, I am unsure of the path forward. From what I’ve gathered, here are some of the known potential issues:
- AC300’s can error / power off / blow when grid AC power is restored while on the Pro/Tran2. This is apparently due to the floating neutral of the AC300, which is not supported by the Pro/Tran2.
- AC300’s AC inverter (out) shuts off when grid is restored.
- Unique considerations are needed for grounding each AC300 member in a 240v split-phase setup (regardless of transfer switch, but compounded by Pro/Tran2).
- Endless debates around floating vs. bonded neutrals, grounding requirements, potential workarounds, unvalidated theories, etc.
- Many more, but my head hurts.
Sadly @BLUETTI has provided absolutely no public support or definitive resolution, only 1-off resolutions with a few of you. As much as I love the AC300’s on their own, I’m starting to believe I have made the wrong decision. A fixed hybrid system would have been up and running by now. But here we are.
So, the ask:
Can we get a CONSOLIDATED thread of WORKING setups and definitive information going? I would be most interested in environments that are using transfer switches or other panel workarounds. Can those who have reached a point of stability share diagrams, lessons learned, products chosen, etc.? E.g.
- are Generac panels the sure way to go? Others?
- Is there a cable configuration that overcomes some of the issues?
- Is there a grounding-based fix?
- Is totally avoiding grid AC input really the right approach?
…and so on.
Also, can @BLUETTI PLEASE CHIME IN?! For f!%*$ sake. We have spent way too much $$ for premium gear to be in this situation.
BTW, a HUGE thanks to all who have contributed to finding resolutions, spending time with Bluetti engineers, testing unreleased code, and risking their gear/time to get answers. I’m a subscriber to your content. Looking at you @Raymondjram, @t4602yf, @t4602yf, @twister36, and so many others.