When I first installed my GT 3.3 back in early December 2006, GT View was showing an
efficiency of 95.3-95.8%%. After about a week or less it dropped
to around the low to mid 93%. (2% loss in efficiency) I've got a
support question in to Xantrex about this matter, but as of yet, I've heard nothing. I was wondering if anyone out there is running GT View, and what efficiency their system is reporting. I've found 2 online web pages that have GT View display real time data and they both are in the 95-96% range. I'm monitoring it for further degradation, but was curious if anyone else has noticed something similar.
I installed the system myself, and haven't changed anything. I would
think the efficiency number is generated by the GT View software,
rather than it being data from the inverter itself, and the
efficiency is the ratio of power in to power out, so it must be an
indication of my GT 3.3 not quite up to snuff, or has gone down hill
so to speak. Anyone with any comments on the matter?
Thanks
Al

I wouldn't worry about it. As you figured out, its Pin / Pout, but keep in mind the GT is not a lab quality power analyzer and is spec'ed to be +/- 1% on the readings plus some fixed value.

I have had other GT inverters also vary by a small amount in reported efficiency over time, but I know for sure its not the unit producing any less power as these units were hooked up to power analyzer, its just the calabration of the reporting circuitry drifting

Thanks for the quick reply! I'm glad to hear that it's just a minor calibration problem, and not the unit starting to go bad. We spend so much effort trying to harvest as much energy as possible, it's disappointing to think it's being wasted as heat.
Best Regards
Al