Yeah, good deal. Now if by some rare chance I come accross some panels Identical to mine, I can add a few more to each string without losses on the suniest days.

Well this is a bummer. They discovered they were wrong and they actually don't have any positive ground inverters in stock of any size. They are going to repair rather than exchange my unit, but they will fully pay for shipping and they will expedite the repairs for me. They said repairs ussually take about a week which is better than I expected, hopefully all goes well.

Ok, the inverter shipped out yesterday, this month has been a month for record rainfall so far. But of course, the first day its offline, the sky opened up and the sun came out bright as ever, figures.

Ok, we just got the inverter back today. I will let everyone know how it is working tommorow after we have the oportunity to try it out, thanks everyone!

The inverter is working and we are back in Buisness! The invoice said they had to change the main power board because it was defective. Had I not had a warranty it would have cost me $545 for the repair and then shipping on top of that. My only problem is that replacing the board reset the lifetime KWH totals. I guess thats minor though, thanks for all the advice everyone!

HEELLLLPPP!!! Ok guys, the inverter worked for 2 days and then went offline with a "Ground Fault" warning and red light. My father is at home describing to me what it is doing. I told him if it signaled a ground fault it should not work again until the fault is found and the fuse is replaced. Apparently he didn't believe me. He turned it off, checked everything himself and turned turned it back on. It kicked back out again after countdown. He then disconnected the first 7 panel string and it came online seemed fine, he then brought the other string online and it's still working. So now I'm confused. If I should believe the manual, this should not happen without blowing the fuse, and it should not come back online without actually fixing anything. I can't imagine where it could have faulted, I'm pretty certain I covered all the bases when I setup the system. Any suggestions? The inverter is online now but it seems as though its putting out about 500watts less than it normally would under today's conditions.

A guess, but if the unit was configured as neg-ground, your inverter would fault when first powered up ... do the the positive grounding of your setup. Once the fuse blows and you reset the inverter, the bond is cleared and unit runs

Check that you have the fuse in the right location ( can be either I believe ) and that's the only difference between the neg/pos ground units

Thanks SG but I already thought of that, I had him take off the cover and look and describe to me what he saw. It was correct for a POS ground system. The fuse is still good apparently. The system is online now and running but appears to be putting out about 500watts less output than it should be. I will check the whole thing top to bottom myself when I get home tonight. It does sound like its running negative ground, which would account for the drop in performance, but it does not appear to be doing so. Normally we get around 2500watts on a sunny day in the summer but we seem to only be getting around 2050watts right now, the sun is unnobstructed right now.

I am going to monitor this thing for another week or so, but the output of the inverter appears to be inferior to what it use to be. We have a 3010 watt array of sunpower panels. On cloudless days (Like Today) durring the summer we would normally see an output of about 2400 to 2800 watts. Since we got this inverter back it has yet to go over 2250. Its averaging about 1600 to 1800 watts. It use to put out that kind of power even with a slight shadow from CB antenna. I don't get it, all wiring appears to be fine. We have not recieved another ground fault warning yet either. Im beginning to suspect there is something wrong with the new main power board. Since these are sunpower panels I suppose there is a possibility that they could have built up some Polarization across panel surfaces, which is why Im going to give it some time. According the literature I have seen, when a system is operated in a negative ground configuration and then changed to positive ground as intended it takes a few weeks for the effect to fully dissapate. As the arrays were not connected to a ground durring the 3 weeks that the inverter was out for repairs, it may have developed a similar condition. Grounding on my system is accomplished in just 1 place, the inverter. I have no ground rods at the array. I grounded the inverter to a ground rod in the basement floor.

Bad time of year to be looking for maximum power, heat will knock things down a bit ... you can check the PV current and see if that looks OK, Also I would check the PV inputs to ground when its running to verify the positive is ground

You can also run single strings as a check to see if one or the other is different , which it shouldn't be. The fact you got a ground fault message is a clue here, that is NOT normal and I have never seen a unit GF and keep running , which points back to the PV in check

And your ground for the GT invetrer should be to your Breaker panel neutral-ground bonding point, not to an independent ground round