question

Lee Moreau avatar image

DIY Solar at home, any options to have the inverter switch to mains power if the battery is low?

I have a Phoenix Inverter 24V 1200VA 120V on my system which has 1kw of solar connected to it with my Lifepo4 batteries, currently just running the fridge in my garage. Is there any option where if the battery gets to a certain level it could switch over to mains power to avoid the fridge turning off, just in case I went several days with no sun where the battery got low? Not sure if that's a feature of the inverter itself or if mine supports that, as this one was pretty much in my budget with anything higher seeming to be overkill.

Alternatively, are there any Victron products like battery chargers, where instead I could have THAT connected to the mains, and when it sees the battery hit a certain voltage or SoC it activates to keep the inverter running? Something like I don't know, if the battery SoC is 30% activate the charger and then stop charging once it's at 50% or something along those lines?

Thanks so much!

chargerPhoenix Invertersolar
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2 Answers
nickdb avatar image
nickdb answered ·

You could replace it with a small multi with a gx (integrated or not).

That’s exactly how ESS works.

2 comments
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Replace the inverter? I just bought it a week ago it's brand new so that's not really feasible unfortunately.
While you can connect a GX to a phoenix for external control, it does not appear to support the ESS assistants which does the automation. You would have been better off with a multi.

I am sure there is a super smart techie here that give some pointers on DIY solutions.

Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

You could install a contactor(2xNO 2xNC to the output of the Phoenix that switches automatically to grid if the Phoenix turns off due to low battery voltage.

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