Switching solar panels with MCU

[rthorntn]

tl;dr can I switch 2.6KW of solar panels between two different inverters using an MCU and relays for under $500.

Hi All,

This is not a "current" requirement I have, I'm not going to be playing with this amount of amps myself.

So say I have eight 325w panels in a string, two strings, these string feed into charger/inverters which supply power to the batteries, it's an off-grid setup.  I also have a seperate grid-connected inverter, let's say that this inverter has no panels connected.

When the sun is beating and I have excess energy production (the batteries are charged), I would like to use an MCU to switch a string of panels to the grid-connected inverter to feed-in.

Obviously this isn't ideal and I should buy a fancy grid-tie charger/inverter but let's just say I inherited the current setup and it works well.

I'm guessing it's an MCU controlling a little relay that's controlling a much bigger relay scenario.

So I guess the question is can you safely switch this connection with an MCU for under $500, I think it would be a maximum of 60A at 48V right?

Cheers
Richard

[wizard69]

Given enough time and money you can do anything you want.   How much damage you cause before you have a working system is the big unknown.   There may be easy approaches to this but that is highly dependent upon what your current system is made of.

The obvious question here is why not just buy a grid tied inverter / charger that already has the required certifications?   I'm generally all for DIY but sometimes the wall to a finished project is just too high for an individual.    That is unless you have lots of time It is sort of like the guys that spend years, even decades, building hot rods in their garages. it can be done but most people just go out and buy a Corvette.