[RE-wrenches] Invert first?

[Jeff Yago]

We have designed and installed many systems like this and do not like running high voltage DC long distances.  We invert at the array and run 240 VAC to the house.  This means the array dis-connects match all the other AC dis-connects and safety switches on the home's exteror  that the utilities and fire department are familiar with using when they need to dis-connect, and AC dis-connects are less costly than the same size rated DC dis-conencts you will need if you keep everything DC from the array.  

As mentioned in other replys, you will land this 240VAC output at the critical loads panel downstream from a battery based inverter.  I think you will find that most grid-tie inverters will provide better performance in selling back to grid.  Have a battery-based inverter  just "hang aroud" on standby waiting for a power outage and keeping the batteries topped off.   Make sure your battery based inverter has way to prevent over-charging batteries during a power outage when using the back feed solar power.  Some inverters do this by shifting the frequency to force the battery inverter to drop off line while others have this as a program feature. 

  Jeffrey Yago, pres.
    DTI Solar Inc.
   (p) 804-457-9566
   (f) 815 846-0677
email -   jryago at dtisolar.com
on the web - www.pvforyou.com



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