Advice for small system grid tied inverter type??

[moeeziqb]

Hello solar folks!
I'm new at solar systems and have 3 - 60w panels and 1 70w panel, all 12v, and would like to put together a small grid tied system with them feeding one or maybe 2 120v circuits in my home which have enough fairly constant loads to use most of the solar power but which would be blocked from backfeeding my smartmeter (and any other house circuits) and of course blocked when the mains were off in an outage etc.
Would like to add this inverter to a larger system maybe in the future so thats a consideration.
Are there any inverters that accomplish this?. My first thought was to simply put a blocking diode ahead of the breaker on each of the circuits fed by the inverter but somehow that seemed too simple to work!
And the grid tied inverters i've found seem to require a min input voltage of 22v so do i gang my 4 panels with 2 panels in series and 2 pairs of these in parrallel to the inverter?
Thanks guys!

[adam2]

Presuming a single phase supply, then once a grid tied inverter is connected to the mains supply, the electricity produced will offset the power drawn from the mains in general.
There is no way of allocating the inverter output to a particular circuit.

Blocking diodes cant be used on AC circuits.

If the grid tied inverter is manufactured to a recognised standard then it WILL feed back into the grid whenever the inverter output exceeds the demand within the premises.
It WONT feed back into the grid lines during an outage or if the mains is out of tolerance regarding voltage or frequency.

You should purchase a grid tie inverter that is approved for use in your country. Use of types NOT approved might be dangerous, or illegal, or it might not work.