SunMAX

cosmicray

So this marketing email pops up in my in-box. Normally I would not take much notice, but the company rolling it out is Ubiquiti ... The same company that makes my wireless  internet remote hardware (which works pretty decently) and I decided to take a closer look. 

https://www.ubnt.com/sunmax/sunmax/

From what I can see, this is a daylight only, no batteries involved, stuff all the excess converted power back back to the grid setup. But what seems (to me) to be different, is that they have a micro-converter mounted on the back of each panel, or perhaps a small group of panels. The various micro-converters are each generating 220V AC (and presumably all are in phase-sync). So there is no DC coming off the roof. I can't decide if that's a good thing or a bad thing.

Any thoughts ?

westbranch

You are right, this IS a GRID TIED system and those micro inverters are common now a days.

vtmaps

westbranch said:

You are right, this IS a GRID TIED system and those micro inverters are common now a days.

And about to become much more common... even for off grid.

Fire departments are very concerned about high DC voltages on roofs.  The NEC is moving toward requiring a way to disconnect solar modules from the ground.   That will be very expensive and difficult if you need to remotely switch off every module from the ground.

On the other hand, if each solar panel has its own microinverter, all you need to do is shut off the main power to the house and all of the microinverters will cease to provide power.  There will be no DC voltages on the roof (except internal to the solar-panel-microinverter unit).

vtMaps

Dave Angelini

I would not want my inverter out in the sun under a panel. Fine for the masses but there are ways to disconnect an array remotely. Most offgrid solar is not on a roof anyway. The firemen I know like that!