[RE-wrenches] Strings and series of batteries

[R Ray Walters]

Problem with bussing in the Flexware, is that the bussbars only go to 1/0. 
(be great if they made an attachment like Sq D, that allowed you to bring bigger cables to their buss.)

Another reason to go to a battery buss instead of cross tying is on complicated layouts where cross tying won't get you even resistance across all strings.
If you have two rows of 5 batteries across the back of the box, and turn two more sideways across the front (for instance), it starts getting weird to set up three balanced strings.
The buss bar method makes it work without any long term performance problems. (and its easier for a tired wrench to figure out in the field)

R. Walters
ray at solarray.com
Solar Engineer




On Dec 2, 2009, at 5:46 PM, Walt Ratterman wrote:

> Michael:
> 
> The bus bar solution has to do at least partially, with:
> 
> - Equal resistance paths to each string of batteries (need to keep the
> circuit cables the same length).
> - Ability to remove (isolate) a string more easily.
> 
> 
> With two strings, if the bus bar capacity exists in the hardware of the
> inverter system (such as the bus in the flexware) simply bring back a large
> battery cable from each of the two strings to the flexware and the bus in
> the flexware becomes the bus bar.  (with a fuse in each positive....)
> 
> Thanks,
> 
> Walt
> SunEnergy Power International