I'm looking for recommendations on an inverter to act as a UPS for a few things in my home. I was really close to just getting a cheaper 6kW Aims/Sigineer/SGP (they're all the same) low frequency unit until I learned that these things are not designed to share a common neutral with the rest of your AC system. The manuals all state that you should never connect the "input neutral" to "output neutral". I've seen a lot of speculation that it would work anyway, with some claiming to have even done this with some of these units, but then there's a whole host of issues surrounding neutral ground bonds with being on inverter power vs pass through. I've seen some highly technical discussions with some speculating that these cheaper Chinese units have cheaped on the input side (they don't even accept input neutral), and so problems can occur on the output side if the output neutral is connected to your main panel neutral in parallel with the grid. I don't really want to get into all of that here, I don't understand much of it anyway, but suffice to say I want to buy a unit where I don't have to worry about any of that and where the unit itself has a neutral input and output that are the same.
The reason I want a low frequency model is I need to power a large sewage pump with an LRA of 57A @ 230V (FLA is 13.7A), and I want there to be as near zero chance as I can get that the inverter would responsible for killing that pump.
So apologies for the long back story, but I'm looking for inverters that can handle 57A @ 230V for <100ms, provide 120/240 split phase output, and have a common neutral architecture. I'd also like to do this for $1500 or less if I can.
So far my top contender is one of the ~4kW Magnum Energy units. These things look like total beasts with whopping 120A (1ms) surge capability, common neutral, and by far the best manual I've seen on any of these (wow what a change from those poorly translated Chinese units). Those are running around $2k and I think I can throw the federal tax credit at that to get the final cost down to $1400. Are there any other companies I should look at? I know there are several like Outback and Samlex, but their inverters that could power this pump are a lot more expensive.
EDIT: Adding a diagram of how I hope to make this work
The reason I want a low frequency model is I need to power a large sewage pump with an LRA of 57A @ 230V (FLA is 13.7A), and I want there to be as near zero chance as I can get that the inverter would responsible for killing that pump.
So apologies for the long back story, but I'm looking for inverters that can handle 57A @ 230V for <100ms, provide 120/240 split phase output, and have a common neutral architecture. I'd also like to do this for $1500 or less if I can.
So far my top contender is one of the ~4kW Magnum Energy units. These things look like total beasts with whopping 120A (1ms) surge capability, common neutral, and by far the best manual I've seen on any of these (wow what a change from those poorly translated Chinese units). Those are running around $2k and I think I can throw the federal tax credit at that to get the final cost down to $1400. Are there any other companies I should look at? I know there are several like Outback and Samlex, but their inverters that could power this pump are a lot more expensive.
EDIT: Adding a diagram of how I hope to make this work
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It has its own capacitor based starter, without it I think the LRA would be even higher. It's a real overkill beast of a pump, but there is no way I'm having that pit opened again and having the pump replaced until it reaches the end of its life, it's a long and messy (literally) story.
