[RE-wrenches] phase issues with SB8000US

[Nik Ponzio]

Wrenchers,

We installed our first SunnyBoy 8000 this month. The customer (happens to be
electrical engineer) is complaining that their computer UPS systems are
tripping whenever the air conditioner (with 120V fan) comes on. This didn't
happen before commissioning the solar system and it doesn't happen when the
inverter is disconnected. So, of course, they suspect the inverter is the
culprit. The theory being that the inverter itself is going out of phase
when one of the legs is loaded down momentarily.

So far, SMA tech support is not agreeing. They are blaming the problem on
the unbalanced loads and/or the UPS systems. Their latest solution is to
move the UPS systems to the other leg. Not surprisingly, the customer is not
impressed with this game of Kick the Can Down the Road.

The inverter does not drop the grid, nor display any error codes when this
happens. This is a 200A, 240V service. The 120V fan draws about 10A
continuously, 40A surge.

Anybody else with similar experiences? Suggestions?

Thanks
Nik

--
Nicholas Ponzio
NABCEP Certified Solar PV Installer

Building Energy
1570 South Brownell Road
Williston, VT 05495
t: 802-859-3384 x15
f: 802-658-3982
c: 802-365-1973
http://www.BuildingEnergyVT.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20100830/51470498/attachment-0002.html>