[RE-wrenches] Charge Control in AC coupled system

[Doug Wells]

Wrenches,

Howie, good to see you probing this issue.
I have an upcoming system as well that is considering a micro-grid approach.
My question would be, is the Outback not able to sell back and charge  
at the same time.  I understand that with power present on the ac  
output terminal the inverter will try to charge the battery.  But  
doesn't the unit also try to sell back on the AC output terminal.   
Most Outback systems will sell down to the float voltage in a battery  
back up situation that is grid connected.  Does all of the DC  
connected array stop selling back with the Sunny Boys going full steam.
For example.  Lets imagine we have 4 kW connected to an Outback dual  
inverter grid connected battery back up and then add 4 kW connected to  
a Sunny Boy in a micro-grid format.  When the sun is shining---and all  
the loads in the critical panel are being met---that the Sunny Boy  
overpowers the Outbacks and 1. Charges the batteries and 2.(my  
question) overpowers the Outback's ability to sell to grid in its  
traditional format?
As always the guidance of the "List" is greatly appreciated.
Thanks


Doug Wells
The Solar Specialists
www.thesolarspecialists.com
802-498-5856