Power-One solar Inverter driving me NUTS!!!

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

On another thought, I recall reading in the manual about the Riso low GFI error. I read that this error of the GFI LED will come on at below 1 megaohm. This would indicate a leakage to ground on the PV side. The way, I understand this, is that the inverter is made to work on 1 megaOhm or above. When I power it on, and it does the RISO check, it comes back at 20 megaohms which is good and normal. So I guess what my point is, the 1 megaOhm that I am reading with the megger when the second board is connected may be normal.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

One more I got. You said you changed that CT? Is it installed facing the right way? What I mean its like a current clamp, face it the wrong way and the measurement is negative.
I think the appreciation goes both ways. Plus you were delivering answers as fast as we asked the questions and you spent many hours as well... never stop learning and thanks to you too for hanging in there when things got tough! I like a little challenge once in a while. Specifically something that is on the rare side of things. It would be nice to figure this out, but without a schematic things aren't looking great as we running out of options.

Hi CapLeaker, by the way I love that handle!! Anyhow, yes I am sure the CT device is installed the correct way. I took extra care with that and made sure I had the new one in hand before removing and unwinding the old. My memory is failing so I did not trust myself and wanted to make it as exact as the old one was.

I did make a mistake with that zener however. I had mistaken it for an 18v zener and replaced it with that value. However I tested the adjacent ones and they measure at 12v. Some other data sheets confirmed this. Not sure if it will make any difference or not but I went ahead and replaced it with a 12 V. However, when I installed it and powered it on, unfortunately, I did not beat the sun and it will not power on because it's dark now. Now I'll have to wait until the morning, oh well, I suppose I need a break anyway. We all do.

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

One more I got. You said you changed that CT? Is it installed facing the right way? What I mean its like a current clamp, face it the wrong way and the measurement is negative.
I think the appreciation goes both ways. Plus you were delivering answers as fast as we asked the questions and you spent many hours as well... never stop learning and thanks to you too for hanging in there when things got tough! I like a little challenge once in a while. Specifically something that is on the rare side of things. It would be nice to figure this out, but without a schematic things aren't looking great as we running out of options.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

I hear ya! Well, if you get any more ideas please don’t hesitate. You have been incredibly helpful and I don’t know how to thank you enough. I know you spent hours of your time in this. I do very much appreciate you!!

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

Dang. Back to the drawing board. Would have been nice to have it fixed. I am out of ideas right now.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

No luck. Still that stubborn GFI LED

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

I don’t want to get my hopes up because I think I tested it before and it was fine. So it may have blown from the megger testing

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

I’ve seen open zeners before. So while it is on the rare side, it’s possible.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

It is 100% definitely open

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

Follow the tracks and see what is connected to that zener. Never mind… saw the pic.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

closest i can find are zener . BZT52C22 . but testing open suggests tvs . never seen diodes fail open . suppose it could happen though

I think it is an 18 V Zener. All the others in that row test fine. I had another 18 V Zener but not SMD so I sorted it in and I'm putting it back together to test. The markings are. WN -3D it looks like but i think the relevent markings are the WN. It is marked exactly the same as the rest so I am assuming it is a Zener just like the rest. I too have never seen one fail open.

[petehall347]

Re: Power-One solar Inverter driving me NUTS!!!

closest i can find are zener . BZT52C22 . but testing open suggests tvs . never seen diodes fail open . suppose it could happen though

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

I think I found something. This dialed circled is testing open in both directions. The remaining are testing fine. Now the question is how to identify it.

This would also make sense in that maybe there isn’t a real ground fault but the detection circuit is wacky. I’ve included a better picture of the markings.

I think you fund something!!!
try cleaning it off with 99% IPA so we can read it better. looks like a diode?

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

I think I found something. This dialed circled is testing open in both directions. The remaining are testing fine. Now the question is how to identify it.

This would also make sense in that maybe there isn't a real ground fault but the detection circuit is wacky. I've included a better picture of the markings.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

If it is a gas discharge arrestor it should be open. If it’s a fuse, then not.

It goes from line to earth ground? If a gas discharge, it’s for lightning protection.

Based on the little information, I have gathered it looks like a gas discharge. I don’t think it’s a fuse, but I can take some better pictures of the numbering on it.

It is denoted with a “V” like the other 4 bulb looking things so I assume it is a gas discharge. If it were a fuse, I would think it would be denoted with a “F“

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

If it is a gas discharge arrestor it should be open. If it’s a fuse, then not.

It goes from line to earth ground? If a gas discharge, it’s for lightning protection.

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

I was previously told it should test open. See thread below.
https://www.badcaps.net/forum/showthread.php?t=124790

It may be that some voltage has to go through it but I fear blowing it if I test wrong.

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

This device I circled in the picture is open?
Verify that one (lower) end is earth ground. If it is earth ground and this device is open, well how is the MOV supposed to work?

[mitsu2k]

Re: Power-One solar Inverter driving me NUTS!!!

check that "v4" device under MOV6.
Other than that I am starting run out of ideas for now.
All the current sensing is done via that CT next to the relays. How ever this is all on the AC side.

How would I check that? It tests open with a DMM.

By the way, I did replace the CT device. Expensive little sucker. Over $30 on AliExpress

[CapLeaker]

Re: Power-One solar Inverter driving me NUTS!!!

check that "v4" device under MOV6.
Other than that I am starting run out of ideas for now.
All the current sensing is done via that CT next to the relays. How ever this is all on the AC side.