Jeff- The Sunny Boys can be reprogrammed into "off grid" mode so they
can work between 56-64 Hz, but I believe you need both a service cable
and a call to SMA tech support to make that happen. They then note in
their system that that inverter's been adjusted to no longer meet UL 1741.
Jeff Yago wrote:
As mentioned before, many of our clients want battery backup with
their solar, but are not off-grid. They also want a generator so
battery banks can be down-sized. For many of these applications we
use a SunnyBoy at the array when the aray is located hundreds of feet
from house, and usually a Xantrex battery based inverter at the
house, and backfeed the solar inverter into the inverter's emergency
loads panel. We pass this backfeed through a heavy duty relay
controlled to open on high battery voltage. Yes, SunnyBoy with
SunnyIsland is better match, but since one is 120 V and the other is
240V that means adding transformers or using two SunnyIslands.
Here is the issue - The SunnyBoy is working perfectly when grid power
is passing back to it through the backfeed connection. However, when
this system operating off-grid when the grid is lost, the SunnyBoy
"sees" the fake grid power coming from the Xantrex which it shows on
L1 and L2 readings, but it is staying in the waiting mode and will
not connect. No errors, just acts like grid a morning startup and
stays that way. I have had problems before with Fronius doing this
and they have provided secret codes to open up the program settings
for the grid which solves the problem when grid power is poor quality
typical at end of line. Is this solution possible with SunnyBoy
inverters, or is there something else going on. Have not had this
problem on other AC coupled systems using the same combination of
inverters.
Thanks,
Jeff Yago
_____________________________________________________________
Netscape. Just the Net You Need.
_______________________________________________ List sponsored by
Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
Options& settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules& etiquette: www.re-wrenches.org/etiquette.htm
Check out participant bios: www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
