[RE-wrenches] Float, Sell Voltages

[holtek at sbcglobal.net]

Trying to tweak a couple of battery based grid-tie systems.Trying to 
maximize sell back without frying or draining the batteries. Have gotten 
various opinions from manufacturer's techs, so why not a few more......
Concord AGM's set now as follows:
Bulk = 57.2v
float = 53.2v
sell = 52v
It is my understanding that sell is actually a "low end float" on a grid-tie 
system and to keep the CC "wide open" for sellback, I might set the float to 
around 54.5v+ ( and maybe even as high as 55v?) and the sell voltage a bit 
higher - (53.2?) with the understanding that if grid goes down for extended 
period of time that the float must be set back to 53.2.  Any thoughts?

One other thing....with 4.3kW PV array, what would you expect as the maximum 
sell wattage to show up at peak sun? (my guess is 3.3 - 3.5)



Holt E. Kelly
Holtek Fireplace & Solar Products
500 Jewell Dr.
Waco TX. 76712
254-751-9111
www.holteksolar.com