[RE-wrenches] AC Coupling

[Larry Brown]

Wrenches,

After Hurricane Irene left a lot of people without power here in the  
Northeast, customers who have grid-tied systems are asking about some  
battery backup to power some essential loads.

We have used Sunny Islands but they require either 2 Sunny Islands or  
a step up transformer to get 240 volts for the well pump.  Schneider  
Electric  (Xantrex XW) inverters look like they would work  for this  
application and do 120/240 volt output as well and we have used these  
in off grid applications but not as AC coupled.  I have considered  
Magnum because they also do 120/240 volts but they need battery  
diversion to ensure the batteries are not over charged.

None of these systems are going to be rewired as a DC system so I am  
looking for any feed back on what others are using to AC couple to  
existing grid-tied systems to provide some battery backup.

Thanks
Larry

Larry Brown
Sun Mountain