Power-One solar Inverter driving me NUTS!!!

[mitsu2k]

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

Here are some more photos with some of the blue caps removed.

[mitsu2k]

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

Something else I noticed: while the instructions tell us to look at the DC side, it looks like all that GFI jazz is done on the AC side? Look at the AC output and follow it straight up. It goes to the CT transformer and the little relay that has something to do with it? Then this goes to these burnt relays. Maybe we are looked at it wrong, since the fault was supposed to be at the DC side. What if some protection device weither shorted or opened on the AC side to Earth ground? Is that maybe why you don't get any error codes on the display, because we aren't looking in the right spot?
At the AC output side there is a blue cap and some round cylindrical protection device, for shitts and giggles check those.
After all, if that is the case, the GFI can't say there is something wrong on the DC because there is no fault there, yet the GFI wouldn't work either making the light come on, because it lost connection to earth ground somewhere else.

“Lost connection to earth ground somewhere”. That is plausible. I know that one of the times I pit it back together and tested, I got a “Riso Low” error which the manual did state is accompanied by the GFI led. Riso Low is the insulation resistance of the panels. I thought I had chapped something but then I realized that I had not put all the screws back in to save time. Once I went back and put put all the screws back in, the Riso Low error went away and it correctly measured Riso at 20mOhms. So you are correct. It could be losing ground somewhere. I will look again in the area you suggested. As far as moisture, I am not too concerned about that because the inverter is mounted indioors in my garage ao that helps.

[CapLeaker]

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

Something else I noticed: while the instructions tell us to look at the DC side, it looks like all that GFI jazz is done on the AC side? Look at the AC output and follow it straight up. It goes to the CT transformer and the little relay that has something to do with it? Then this goes to these burnt relays. Maybe we are looked at it wrong, since the fault was supposed to be at the DC side. What if some protection device weither shorted or opened on the AC side to Earth ground? Is that maybe why you don’t get any error codes on the display, because we aren’t looking in the right spot?
At the AC output side there is a blue cap and some round cylindrical protection device, for shitts and giggles check those.
After all, if that is the case, the GFI can’t say there is something wrong on the DC because there is no fault there, yet the GFI wouldn’t work either making the light come on, because it lost connection to earth ground somewhere else.

[CapLeaker]

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

Oh boy, there is a lot of black PCP that would needed to be cut out, filled etc. it’s all exposed too ready to hold moisture… with a lot of DC power going through it, not good. I also seen a few little via’s that look a little sad.

[mitsu2k]

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

OK I just want to be thorough and follow your suggestions so I have removed the relays, unfortunately I did a little bit more damage in the process but that’s OK. Anyhow, the photos are attached.

I did check for continuity between all top holes and bottom holes after removing the relays and had continuity through on all 16 holes.

[mitsu2k]

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

I have this happened to in the past working on a board that several relays had bad pin connections and it was a multi layer board the top layer was not getting any solder on the top layer but only the bottom layer because the trace in between was not there anymore and it drove me nuts to figure out why this board was not working properly

I would highly recommend removing all the relays and very closely look at solder traces between the top layer and the bottom layer and see if it looks like there should be one or not

I not suggesting that are but some time when the bottom traces are gone and there is a top trace the solder does not travel to the top trust me I have happened to me several times in the past

SAM, I have not yet removed the relays to look again, but previously I have looked several times. I am just a little hesitant to keep removing them and re-soldering them because the pads are getting pretty worn out. But the traces are pretty large and even if one of them does not make contact on the top, it still makes contact on the bottom to the same components. I did verify that by testing for continuity from the top against the bottom. However, these relays are on the A/C side of the unit and our problem seems to be on the DC side.

Also I need to mention that the burnouts were always on the high voltage contact sides of the relays. There are two pairs of relays. I will call them the top pair and bottom pair depending on how are looking at the board. On each pair, only one relay is getting the 12v to turn on. I tested this by connecting some jumper leads to the coil side of the relays and extending the wire outside of the board for testing. However this is likely normal because a GFI error dissconnects the grid side of the inverter.

[mitsu2k]

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

Out of curiosity: The two 60V PSU's you are using to start the inverter, they aren't earth grounded on the negative? Just saying if you use one or two linear power supplies that have an earth pin on the power mains plug, the negative coming out of the PSU is coupled to earth ground.
Keep this in mind, that you may need a isolation transformer on these power supplies.

No they are not earth grounded on the negative. I actually an not using those anymore. I had borrowed them from a friend, so I had to return those. As it stands, I am just reconnecting it to the array to power it on.

[sam_sam_sam]

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

But as far as I can tell, the bottom and top are carbon copies of eachother so just the bottom connected should be sufficient. However, I got nothing to lose. I will remove all the relays and check again. It is possible I'm missing something.

You need to take a meter and check each relay trace that has a connection on the top and bottom on that pin and make sure that you have connection between the two of them if not there would probably be an issue if there is not a lot of current on that pin you can take a strand of wire and put it in the pin hole and solder it to the trace on the top to the bottom trace now if you have a lot of current on the relay pins this is going to be more difficult to do ( unless the traces are some what big enough to enlarge the pin holes and put several strand’s around the pin hole to be able to handle more current )

One solution might be is to put the relay on a separate board and keep the hook up wires as short as possible I personally have not had to do this before so I am sure what kind-a of success rate you would have doing it this way would be

Please take a picture of top and bottom of the board with out the relays in place and I might be able to give you some suggestions for a solution to your problem

[CapLeaker]

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

Out of curiosity: The two 60V PSU's you are using to start the inverter, they aren't earth grounded on the negative? Just saying if you use one or two linear power supplies that have an earth pin on the power mains plug, the negative coming out of the PSU is coupled to earth ground.
Keep this in mind, that you may need a isolation transformer on these power supplies.

[mitsu2k]

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

I have this happened to in the past working on a board that several relays had bad pin connections and it was a multi layer board the top layer was not getting any solder on the top layer but only the bottom layer because the trace in between was not there anymore and it drove me nuts to figure out why this board was not working properly

I would highly recommend removing all the relays and very closely look at solder traces between the top layer and the bottom layer and see if it looks like there should be one or not

I not suggesting that are but some time when the bottom traces are gone and there is a top trace the solder does not travel to the top trust me I have happened to me several times in the past

I know for sure that some of the contact pads on some of those relays are completely separated between the top and bottom pads due to the burning out. But as far as I can tell, the bottom and top are carbon copies of eachother so just the bottom connected should be sufficient. However, I got nothing to lose. I will remove all the relays and check again. It is possible I'm missing something.

[mitsu2k]

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

On the second board, I installed it without plugging in any of the wires. I checked for continuity between earth ground and all of the wire terminals on the board. Found no continuity to ground to any of the terminals.

[mitsu2k]

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

I removed a bunch of those caps connected to ground and tested them with the megger. Not sure if that is a proper test but they all showed over 4000 megaOhms. Except for the two large white ones (30uF) on the main board. Those initially came back over 4000 megaOhms but after about 7-8 seconds they started dropping. I did not wait to see how far they dropped but they were dropping pretty steadily.

[mitsu2k]

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

Most of the time they are module that many pins on it but the only way to be sure that it is a IGBT module is to google it

I forgot the “B” sorry about that

There are two of these on the board with the 4 large capacitors.
https://cdn.badcaps-static.com/pdfs/...f9e4568a9c.pdf

Also these 7 guys circled in the other pic have no part number on top

[sam_sam_sam]

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

I’m sorry, what is the IGT module? I can take a pic

Most of the time they are module that many pins on it but the only way to be sure that it is a IGBT module is to google it

I forgot the “B” sorry about that

[sam_sam_sam]

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

I have this happened to in the past working on a board that several relays had bad pin connections and it was a multi layer board the top layer was not getting any solder on the top layer but only the bottom layer because the trace in between was not there anymore and it drove me nuts to figure out why this board was not working properly

I would highly recommend removing all the relays and very closely look at solder traces between the top layer and the bottom layer and see if it looks like there should be one or not

I not suggesting that are but some time when the bottom traces are gone and there is a top trace the solder does not travel to the top trust me I have happened to me several times in the past

[mitsu2k]

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

The first board all I can see is a double layer board. The second board is at least 3 layers. No problem for writing that post again. It's very interesting how this inverter works. MPPT is complicated, but more efficient. Anyway… would be too nice to find a service manual with schematics for this thing.

Schematics would be great but I have not been able to find any and the company has sold several times. And yes you are correct. This is one complicated sucker

[mitsu2k]

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

Is there any part numbers on the IGT module if there is can you please post it thanks

Because depending on the model number sometimes there is a test procedure for that particular one

I'm sorry, what is the IGT module? I can take a pic

[CapLeaker]

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

The first board all I can see is a double layer board. The second board is at least 3 layers. No problem for writing that post again. It’s very interesting how this inverter works. MPPT is complicated, but more efficient. Anyway… would be too nice to find a service manual with schematics for this thing.

[sam_sam_sam]

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

Is there any part numbers on the IGBT module if there is can you please post it thanks

Because depending on the model number sometimes there is a test procedure for that particular one

[mitsu2k]

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

on another thought, I wonder if that main board is also a 3 or 4 layer PCB. If so, I may have a problem with connection on the pins that the relay burned out.



Edit: that main board does not appear to have any layers within. Just top and bottom that I can tell.