Renesola Micro Inverter / Panal Issue - Help

[Chuck W.]

I've search past posting here and can't find an answer.

I have a 10 kW 40 panel solar set up using Renesola panels and micro inverters. A month ago one of the panels started out producing very little then quickly went to zero. The status of the inverter showed OK. I removed the inverter and test the output of the panel and it was producing. I swapped out the inverter putting a brand new one in its place. I entered the new units serial number into the base and I am now getting "0x8000" indicating that it is not getting any power at all. The LED light on the inverter blinks slowly indicting an issue.

So, if it isn't the panel and it isn't the inverter what am I missing?

[sdold]

Did you measure the short circuit current of the panel in full sun? It's possible that it could produce near Voc but not be able to supply the current.

[J.P.M.]

If you did not do the install, have you contacted the installer and asked them ?

[Chuck W.]

Did you measure the short circuit current of the panel in full sun? It's possible that it could produce near Voc but not be able to supply the current.

Yes, it was in full sun.

If you did not do the install, have you contacted the installer and asked them ?

Yes and no.... I was the grunt labor and a buddy and his son installed them. They have since moved.

I appreciate both comments and welcome others.

I have a spare panel I am thinking of dragging up to the roof and plugging it in to see if the panel itself is bad.

[sdold]

Yes, it was in full sun.

I understand that you measured it in full sun, but did you measure the short circuit current, or just the voltage? If so, what was it?

[Chuck W.]

I understand that you measured it in full sun, but did you measure the short circuit current, or just the voltage? If so, what was it?

Just over 30 volts.

[sdold]

Did you measure the short circuit current of the panel in full sun? It's possible that it could produce near Voc but not be able to supply the current.

[Chuck W.]

Did you measure the short circuit current of the panel in full sun? It's possible that it could produce near Voc but not be able to supply the current.

I am sorry.... but I am not very knowledgeable regarding "near VOC". It did measure over 30 volts in full sun.

Today I drug a new panel to the roof (2-story, ugh...) and plugged it in in place of the one not producing. Same results, no power. The inverter (the second one I have replaced the original one with) LED is blinking slowly indicating a power issue.

I am at a lose.... replaced the inverter and now the panel and have reentered the inverter number twice in the system and still getting 0x8000 / no power.

[sdold]

There should be a label on the panel listing Voc, Isc and some other things. Voc is "Voltage, open circuit" and it's roughly the voltage you would measure across the unconnected (open circuit) panel wires if the panel was in full, direct sun. It sounds like you measured the voltage under load (to the inverter) instead. Unconnected, your panel's Voc should be around 37 volts.

Isc means "I (current), short-circuit" which is the current in amps (I) through the leads if they are shorted together, either directly or through an ammeter (your meter set to measure "amps"). It's another measure of the health of a panel, because it's possible a panel could generate near its rated Voc, but not be able to produce the current (amps).

But it sounds like you (hopefully) ruled out that possibility by substituting another (hopefully good) panel. Since you've swapped out both the panel and inverter, at this point I think I'd suspect the inverter's connection to the trunk cable, or mis-configuration of the new inverter.

[Chuck W.]

I always dislike it when a thread is started with an issue and there is never any closure. The closure on my issues were the panels. Oddly, three panels have gone bad. If you put a meter on them they all show >32 volts but they were not powering the mirco inverters. I replaced one panel at a time and they were indeed this problem. Everything I have read, it is unusual for panels to go bad. These panel are on the roof and not close to each other. Very odd all the way around.

[sdold]

Thanks for the followup, you're right, we often don't get to see the resolution. I used Rennesola in my system in 2014 and sold the house a year ago. I seem to remember trying to find the company on line a year or so ago and not seeing anything, as if they had gone out of business. Did you replace them with another brand?

[Chuck W.]

Did you replace them with another brand?

Yes. I have lost all confidence in Renesola. I bought new Talesun panels I found on Craigslist. No doubt they are the same quality as Renesola but by a different name.