[SOLVED] 18kpv loud bang on day 3 of operation

[jorby]

Did Art really run that high? I (K7WLD) was listening to him once a few years ago when he turned his amp on and off, and it was a stronger signal, but I didn't notice any supernova effects. Was he known to run many kw's ?

I have no idea about the power he actually used but the night I heard him on 80 meters, his was the strongest signal that I had ever heard at 60db over s9. Compared to the other signals at s9, it was as if God had spoken up. I was impressed. Double power is 3db and an S-unit is 6db (4 times the power) and 10db is 10 times the power. So if everyone else was only using 100w @s9, and 1000 w at 10db over s9, it would take 10,000w to get to 20db over and 100,000w to get to 30db over. Most hams don't even have access to that much power from the grid. A 200a service can go to 48kw and at 66% efficiency an amplifier could do 32kw output continuously. Perhaps I was just at the sweet spot for skip that night.

 

[EG4TechSolutionsTeam]

The PV voltage should have been recorded up to 600V, accompanied by a Bus Voltage High and PV Voltage High error.




While I would recommend sizing the array for the operational range, damage should not occur as long as the voltage stayed below 600V. Though this is a bit late, how was the system wired? Additionally, were ISO and PV Arc enabled to detect potential issues like low insulation or arc faults caused by damage or loose wiring?

 

[Deere103]

The PV voltage should have been recorded up to 600V, accompanied by a Bus Voltage High and PV Voltage High error.

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While I would recommend sizing the array for the operational range, damage should not occur as long as the voltage stayed below 600V. Though this is a bit late, how was the system wired? Additionally, were ISO and PV Arc enabled to detect potential issues like low insulation or arc faults caused by damage or loose wiring?

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Thanks, it seems there is still some confusion here as I was just assured by signature solar on monday that the unit disconnects above 500vdc. in any case, to answer your question:

PV arc - yes

Iso - doubtful, I'm not familiar with this setting and can't find it in my remote set PDF export.

is there a downside to enabling these features? I'm just curious why they aren't enabled by default?

as far as wiring, I'm guessing you mean the PV wiring?

I originally had an array of 12 panels in series, ~45 Voc @ std conditions. ~ 11 amps Isc ; wire run is 10 AWG PV wire ~ 300 ft.

final plan is 2 arrays of 12 panels into PV input 1 and paralleled in unit. However, I have since reduced the panel string to 11 panels and will wait on clarity on this Voc max matter and behavior above 500 vdc. We don't have many cold days in my area so prefer to run on upper voltage range and panel array size to maximize output and to aid in my longish cable run.

thanks

 

[wpns]

seems there is still some confusion here as I was just assured by signature solar on monday that the unit disconnects above 500vdc

Unfortunately, Signature Solar is not a single monolithic entity, nor is it one person. Depending on who you talk to, when you talk to them, and their knowledge about your exact question, you may get a different answer from a different person on a different day.

I know for a fact (see above) that my 18Kpv running firmware FAAB-1B1C continues to produce power above 500 V

 

[SignatureSolarJess]

Hi @Deere103 - Leila is just waiting on the tech bench report from EG4 for your RMA but we will update you as soon as we receive it! We will ensure that our team is aligned on this. Thank you so much for letting us know!

 

[455dan]

Unfortunately, Signature Solar is not a single monolithic entity, nor is it one person. Depending on who you talk to, when you talk to them, and their knowledge about your exact question, you may get a different answer from a different person on a different day.

I know for a fact (see above) that my 18Kpv running firmware FAAB-1B1C continues to produce power above 500 V

Yes, different people different advice, I was told by Clay at Signature Solar during purchase to stick with 8 string series of the kit included 49 Voc panels for the 18 K with cold temps that have hit -30 F, that made a lot of sense. Checking a string this morning overcast seeing just about 399 volts and temps are high 20's.

I was somewhat shocked when EG 4 released that solar panel calculator ap, and using the same info it said I could squeak by and series ten....
That just seems like asking for trouble, especially if the Electrolytic caps are in circuit that were shown earlier in the thread, maxing out at just barely over 600 volts when paired.
Caps also have +- tolerances on Voltage just like they do for capacitance, imo the ap is cutting it to close for comfort after reading this thread, and Not saying that over voltage the cause of the Op's failure.
Running the 18K at a slightly lower series array voltage seems like a better Safe than Sorry approach going forward for me as a Newby to Solar.

 

[jorby]

Yes, different people different advice, I was told by Clay at Signature Solar during purchase to stick with 8 string series of the kit included 49 Voc panels for the 18 K with cold temps that have hit -30 F, that made a lot of sense. Checking a string this morning overcast seeing just about 399 volts and temps are high 20's.

I was somewhat shocked when EG 4 released that solar panel calculator ap, and using the same info it said I could squeak by and series ten....
That just seems like asking for trouble, especially if the Electrolytic caps are in circuit that were shown earlier in the thread, maxing out at just barely over 600 volts when paired.
Caps also have +- tolerances on Voltage just like they do for capacitance, imo the ap is cutting it to close for comfort after reading this thread, and Not saying that over voltage the cause of the Op's failure.
Running the 18K at a slightly lower series array voltage seems like a better Safe than Sorry approach going forward for me as a Newby to Solar.

As an owner of one of these, I am eager to hear whether it was the capacitors, an MOV or FET/igbt (or some combination) that actually failed. Since it has been reported that it doesn't work on pv3 either, it seems like there is more broken than just the input capacitors of pv2. I would be snaking my inspection camera up in there to see where the carnage is.

 

[BKY2003]

Looking at your settings, does this indicate that the 3 PV was the only independent one? I believe mine has all 3 as independent. Mine is number 7. Which might have nothing to do with anything, but it just stuck out to me.

 

[jorby]

Looking at your settings, does this indicate that the 3 PV was the only independent one? I believe mine has all 3 as independent. Mine is number 7. Which might have nothing to do with anything, but it just stuck out to me.

Setting #3 indicates that only pv3 is in use. Setting #7 is for all three in use. There are other numbers for combinations of usage. OP had been using #2 when it blew up and changed to #3 to see if it would work, but there were problems with it. If I recall correctly.... The three mppt are independant as to running from different panel strings which can have different voltages, but still work together to charge the 400v buss when you go with setting 7.

 

[jorby]

Setting #3 indicates that only pv3 is in use. Setting #7 is for all three in use. There are other numbers for combinations of usage. OP had been using #2 when it blew up and changed to #3 to see if it would work, but there were problems with it. If I recall correctly.... The three mppt are independant as to running from different panel strings which can have different voltages, but still work together to charge the 400v buss when you go with setting 7.

The fact that all 3 mppt drive one 400v buss is why I am thinking there is more trouble than just the input capacitors. A blown fet could be pulling the bus down like was shown in one of the graphs that was posted. That would make pv1 and pv3 not be able to function properly. OP was wise to stop any further attempts to use the other mppt.

 

[fnnwizard]

As an owner of one of these, I am eager to hear whether it was the capacitors, an MOV or FET/igbt (or some combination) that actually failed. Since it has been reported that it doesn't work on pv3 either, it seems like there is more broken than just the input capacitors of pv2. I would be snaking my inspection camera up in there to see where the carnage is.

Yeah, I would love to know what EG4 finds.

After seeing the logs I have been thinking it's not likely mppt failure.

I doubt any of the HVBus caps failed since V shouldn't have gotten above 600V, and usually there would be more smoke from something that big.

What I thought at first as y class capacitors blowing is more likely an MOV because it's DC on that board, but I don't think that failed either since the logs showed mppt #2 to work fine afterwards.

Most likely, with the current data, it is pointing towards fet(s)/igbt(s). I never opened that side of the inverter and wonder what brand they used.

 

[EG4TechSolutionsTeam]

Thanks, it seems there is still some confusion here as I was just assured by signature solar on monday that the unit disconnects above 500vdc. in any case, to answer your question:

PV arc - yes

Iso - doubtful, I'm not familiar with this setting and can't find it in my remote set PDF export.

is there a downside to enabling these features? I'm just curious why they aren't enabled by default?

as far as wiring, I'm guessing you mean the PV wiring?

I originally had an array of 12 panels in series, ~45 Voc @ std conditions. ~ 11 amps Isc ; wire run is 10 AWG PV wire ~ 300 ft.

final plan is 2 arrays of 12 panels into PV input 1 and paralleled in unit. However, I have since reduced the panel string to 11 panels and will wait on clarity on this Voc max matter and behavior above 500 vdc. We don't have many cold days in my area so prefer to run on upper voltage range and panel array size to maximize output and to aid in my longish cable run.

thanks

I believe ISO may need to be enabled on the LCD display, but there are no significant downsides to enabling it. Without inspecting the wiring, it’s difficult to determine what might have gone wrong. However, the loads should remain powered, and no damage should occur to the MPPT unless the voltage exceeds 600V. Personally, I believe that the 12 panels in series would be fine unless you are planning on seeing temperatures below 15°F.

 

[Deere103]

I believe ISO may need to be enabled on the LCD display, but there are no significant downsides to enabling it. Without inspecting the wiring, it’s difficult to determine what might have gone wrong. However, the loads should remain powered, and no damage should occur to the MPPT unless the voltage exceeds 600V. Personally, I believe that the 12 panels in series would be fine unless you are planning on seeing temperatures below 15°F.

you and me both, but it is an unpopular opinion...haha..

thanks for the info, I'm waiting on the "tech bench report" to receive an RMA from EG4...any idea how long this process usually takes? I'm a week in since deciding the unit needs to be a warranty claim and no updates on this.

 

[EG4TechSolutionsTeam]

you and me both, but it is an unpopular opinion...haha..

thanks for the info, I'm waiting on the "tech bench report" to receive an RMA from EG4...any idea how long this process usually takes? I'm a week in since deciding the unit needs to be a warranty claim and no updates on this.

I’ll reach out via DM to gather more details and confirm a timeline.

 

[Deere103]

got a notification that a shipment coming from SS, hoping to install while I have some time at home over Christmas; thanks for everyone's help here and I'll post all the settings for peer review before flipping the switch just so I don't overlook anything. Merry Christmas everyone and thank you EG4 and SS for not giving me too much grief and making things right!

One thing to chew on, SS recommended I isolate my PV grounds from my main power. in my case the panels are mounted on a steel building roof about 300 ft from my home. This building has it's on power service and ground rods (2 spaced 6 ft apart in my area). Currently I have the panel frames grounded to these rods and then in the conduit with the PV conductors to house. The ground then ties in to the ground at my home service which is what is code and my understanding of best practices. I'm not opposed to only grounding at the shop ground rods, just wanted to know everyone's thoughts? I've watched some of MIke Holts vids on this, but my ground rods are pretty far apart between the services so not sure there's a ton of problem with potential differences. We have summer storms, but I wouldn't say I'm in a high risk area for crazy lighting strikes like TX per say.

Also, I have a standard PV disconnect at the shop, but I'm going to be adding a separate disconnect with surge protection while I'm doing the final wiring. I know it doesn't solve a many problems, but it's easy to install, has some redundancy, and doesn't hurt.

Thanks

 

[BKY2003]

When SS was trouble shooting your 18Kpv did they ever say if reverse polarity protection was added? I remember at one time they said the 18Kpv did not have it, just wondering if that came up?

 

[jorby]

got a notification that a shipment coming from SS, hoping to install while I have some time at home over Christmas; thanks for everyone's help here and I'll post all the settings for peer review before flipping the switch just so I don't overlook anything. Merry Christmas everyone and thank you EG4 and SS for not giving me too much grief and making things right!

One thing to chew on, SS recommended I isolate my PV grounds from my main power. in my case the panels are mounted on a steel building roof about 300 ft from my home. This building has it's on power service and ground rods (2 spaced 6 ft apart in my area). Currently I have the panel frames grounded to these rods and then in the conduit with the PV conductors to house. The ground then ties in to the ground at my home service which is what is code and my understanding of best practices. I'm not opposed to only grounding at the shop ground rods, just wanted to know everyone's thoughts? I've watched some of MIke Holts vids on this, but my ground rods are pretty far apart between the services so not sure there's a ton of problem with potential differences. We have summer storms, but I wouldn't say I'm in a high risk area for crazy lighting strikes like TX per say.

Also, I have a standard PV disconnect at the shop, but I'm going to be adding a separate disconnect with surge protection while I'm doing the final wiring. I know it doesn't solve a many problems, but it's easy to install, has some redundancy, and doesn't hurt.

Thanks

The farther apart the ground systems are, it seem likely that potential difference could be greater during an electrical storm. Having them tied together keeps that under control. It would be interesting to monitor current on the wire that connects the ground systems during a storm. Just thinking out loud here....

I doubt that this was relevant to the failure to begin with.

 

[wpns]

interesting to monitor current on the wire that connects the ground systems during a storm

Yeah, clamp-on ammeter with peak reading , just make sure you are looking at it during the lightning strike. ️

 

[Deere103]

When SS was trouble shooting your 18Kpv did they ever say if reverse polarity protection was added? I remember at one time they said the 18Kpv did not have it, just wondering if that came up?

This wasn't discussed during the diagnosis, so I'm not sure, I'm definitely not testing it, just double and triple checking haha

 

[Deere103]

The farther apart the ground systems are, it seem likely that potential difference could be greater during an electrical storm. Having them tied together keeps that under control. It would be interesting to monitor current on the wire that connects the ground systems during a storm. Just thinking out loud here....

I doubt that this was relevant to the failure to begin with.

Yeah no storms anywhere in the area for a while now, was just something they brought up when reviewing my wiring

 

[fnnwizard]

I'll post all the settings for peer review before flipping the switch just so I don't overlook anything.

Settings and pics go a long way to help identify possible issues, so very good idea!

BTW, I looked up those Capacitors and the 630V (2x315V) is a continuous V rating. Their surge rating is 730V! (2x365V)

 

[455dan]

Settings and pics go a long way to help identify possible issues, so very good idea!

BTW, I looked up those Capacitors and the 630V (2x315V) is a continuous V rating. Their surge rating is 730V! (2x365V)

That is VERY Good to hear.

 

[Quattrohead]

Even the skeptical amongst us are starting to realize these things are built like serious brick out houses. Very, very impressive hardware and still improving firmware.
I don't need convincing but the skeptical should feel warm and fuzzy about these units long-term.

 

[EZPZ]

Not in my case. I export up to 12kW so there is always a place for power to go. For me anyway it happens when low soc% and also at 100%. I am looking through my data now…

So I removed one panel from one of the arrays. Made no difference to the occasional drop out of pv watts getting generated. Also tried “no pv” etc and made no difference either.

 

[EZPZ]

So I removed one panel from one of the arrays. Made no difference to the occasional drop out of pv watts getting generated. Also tried “no pv” etc and made no difference either.

Completely sunny day all day