Sol-Ark 15k will only invert 13k of DC PV to AC

[themizz]

With all due respect to everyone who wants to rehash this argument over and over between Deye and Sol-Ark and who developed what.

I think we should take it from the horses mouth here: https://diysolarforum.com/threads/sunsynk-max-16-kw.35458/post-498891 As @Keith Gough states:

"Not quite correct, the inverter was developed with 3 companies Solar Ark, Sunsynk and Deye
That’s why we have three completely different operating systems"

Anybody can interpret that as they will, but my interpretation would be that the base level firmware is developed by the manufacturer (Deye) and Sol-Ark, Deye and Sunsynk add UI and feature enhancements as they wish. The base feature set and capabilities are pretty much identical on each unit from what I can tell.

In terms of the pricing argument, the fair comparison would be Sunsynk vs Solark as they both have English language support, engineering and warranty.

Here is a 16KW Sunsynk for example: https://www.solarwaysuppliers.co.za/product/sunsynk-16kw-single-phase-inverter/ ...comes out to around $4,000 US.

 

[629658]

With all due respect to everyone who wants to rehash this argument over and over between Deye and Sol-Ark and who developed what.

I think we should take it from the horses mouth here: https://diysolarforum.com/threads/sunsynk-max-16-kw.35458/post-498891 As @Keith Gough states:

"Not quite correct, the inverter was developed with 3 companies Solar Ark, Sunsynk and Deye
That’s why we have three completely different operating systems"

Anybody can interpret that as they will, but my interpretation would be that the base level firmware is developed by the manufacturer (Deye) and Sol-Ark, Deye and Sunsynk add UI and feature enhancements as they wish. The base feature set and capabilities are pretty much identical on each unit from what I can tell.

In terms of the pricing argument, the fair comparison would be Sunsynk vs Solark as they both have English language support, engineering and warranty.

Here is a 16KW Sunsynk for example: https://www.solarwaysuppliers.co.za/product/sunsynk-16kw-single-phase-inverter/ ...comes out to around $4,000 US.

What you are missing is UL listed and split phase. Without both off grid applications only. So the Sol Ark is your only option at this time within the USA for grid connected applications. So what dollar value should be assigned to that as well as 24/7 tech support and 10 yr warranty. Roughly $3000 price difference. FTC alone that brings price difference to $2000 or less so the question is is it worth $2000 for the Sol Ark. Those of us that have them the answer is obviously yes.

 

[themizz]

What you are missing is UL listed and split phase. Without both off grid applications only. So the Sol Ark is your only option at this time within the USA for grid connected applications. So what dollar value should be assigned to that as well as 24/7 tech support and 10 yr warranty. Roughly $3000 price difference. FTC alone that brings price difference to $2000 or less so the question is is it worth $2000 for the Sol Ark. Those of us that have them the answer is obviously yes.

That is not really the point I was making. Yes of course those aren't split phase or UL listed.

The point is Sunsynk has gone through similar certification processes in the many countries they serve and also provides warranty support and tech support, yet they are able to sell (presumably at a profit ) the same unit (the cost of the hardware to make split phase vs single phase is nominal)

The price differential between the sunsynk and solark can only really be explained by non-market (lawyers) forces.

If people want to pay solark a premium for the benefits you listed they should be able to but to exclude Deye from the US market is hurting consumers.

Sunsynk goes head to head with Deye in the markers they sell in and charges a small premium for what would assume is their superior warranty and support vs Deye's. If Sunsynk can operate in a competitive environment profitability there is no reason Solark can't either.

The intellectual property arguments to exclude Deye sale in the US seems bogus to me in light of what @Keith Gough has publicly stated on this forum.

 

[629658]

That is not really the point I was making. Yes of course those aren't split phase or UL listed.

The point is Sunsynk has gone through similar certification processes in the many countries they serve and also provides warranty support and tech support, yet they are able to sell (presumably at a profit ) the same unit (the cost of the hardware to make split phase vs single phase is nominal)

The price differential between the sunsynk and solark can only really be explained by non-market (lawyers) forces.

If people want to pay solark a premium for the benefits you listed they should be able to but to exclude Deye from the US market is hurting consumers.

Sunsynk goes head to head with Deye in the markers they sell in and charges a small premium for what would assume is their superior warranty and support vs Deye's. If Sunsynk can operate in a competitive environment profitability there is no reason Solark can't either.

The intellectual property arguments to exclude Deye sale in the US seems bogus to me in light of what @Keith Gough has publicly stated on this forum.

Questioning the reasons is beyond my concern. If Deye and Sunsync which to go through the UL certification process I guess they could but it costs time and money. For whatever reason they have elected not to do so. Sol Arks marketing is completely in line with other manufacturers. Have you looked at overseas pharmaceuticals? At least 10 times more expensive in the USA than overseas for the same meds. So I tend to be a big picture person and I have too much on my plate to sweat Sol Arks costs or marketing. At the end of the day did I want to pay another $2000 for the Sol Ark? Not especially but I recognized the value and did it because I wanted the features they offered. But I didn’t spend hours in a forum complaining about it. I either pulled the trigger or I didn’t. I did because the alternative was not an option for us.

 

[629658]

The world is as it is I change the things I can and accept the things I can’t. But those of us that have Sol Arks for the most part love them. Those that do not own Sol Arks cannot seem to accept the realities of the situation and spend a tremendous amount of their time rehashing the same dead horse the Sol Ark costs too much and I won’t pay it which is fine but others are standing in line to scoop them up. So if you choose not to purchase one fine great grand and we support your decision but most of us have had our fill of Sol Ark is too expensive. We would simply ask you to accept our decision to purchase the Sol Ark. I mean amortization on that additional $2000 over the life of the inverter is what $120 a year? So you’re going to install a less featured inverter over $10 a month? I mean I guess if it bothers you that much then yes but I will gladly pay it and use the additional features and amenities. I would say you are throwing out the baby with the bath water.

 

[Clint-L]

We ought to try and keep this thread clean for discussion of the PV production issue/research as to why PV-DC maxes at just over 13.2kw and why when we first hit full sun at hit that threshold in the mornings we see the PV drop down to nearly zero and ramp back up several times. Then it seems to stabilize.

This is the problems I’ve been working on for 6 months now.

Sol-Ark replaced the inverter. The newer 15k model did have lugs instead of screws like a car steep power amp - ??. Otherwise it is the same.

What was brought up earlier is yes the micro inverters I’ve added gives me a helpful control group. I’ll see the PV- DC drop to zero during that first full sun around 11:40am currently and the micros are just running full force. Once things stabilize the unit produces a clipped max PV-DC of 13.2~Kw.

I’m about to the point of just taking one of my three arrays piping it in to a different inverter like a UL certified Growatt and just accepting the fact that I cannot get what they advertise for the 15k.

If I pull one array out of the three (doesn’t matter which one) they other two can produce around 12kw. Each of the three arrays are max @6.4kw each. This is probably my next project I suppose. I’ll just send one array until a growatt or something and put the AC output of that new inverter going in the smart / micro AC input on the Sol-Arc 15k. Then I’ll just have to keep my chin up and be past this.

All in all, I really do think the Sol-Arcs are good, but this 15k seems to have been branded something that it cannot do, at least not in my use case with my panels.

Sol-Arc’s last thing was they wanted pictures of my panel install, yet I can prove each array can output around 6.2kw or so with full sun and the throttle is obviously not a panel / array issue.

In the end, I’m disappointed about the money spent and not being able to really do what was promised. Im kind of stuck with it at this point.

My last thoughts are this —- if I did this all over again, I feel like I would probably still buy the 15k, but I’d have the expectation to treat some of their ratings like an old off brand car stereo amp that says 1,000watts, but yet in the end we know that it’s only maybe 75watts RMS at a reasonable THD level. ??????

If anything changes I’ll let the group know and I’ll continue to monitor the thread.

It would be super nice if we didn’t continue to clog this thread with the other topics. We could start a new thread? ???

I’m all about let’s talk about it, but hopefully we can keep our topics relevant to each thread. Not trying to complain, I’m just thinking about other folks researching and maybe having the same issue and they try to read through our thread here and see a bunch of us not only arguing, but arguing about things completely unrelated.

I want to thank everyone that helped me through all of the troubleshooting and I will even thank Sol-ark for trying even though they failed to deliver a fix.

On a positive note, since I believe several folks think it’s a software issue (including me) I’ll keep my hopes up that they will magically correct the issue soon. The 15k has only been out for like 8 months or something. I bought my original as soon as they hit the distribution channel.

 

[SolarRich]

In your chart at the time you have marked with the cursor - 13:45, PV is producing 63 watts while microinverters are at 1799watts. So it looks like at this point the DC PV input to the inverter is producing almost nothing while the microinverters are continuing to produce.
How many watts of panels are now wired to the microinverters?
I'd like to see a chart of your Sol-Ark PV volts and amps for the same time period as that chart. I think we would see PV volts spiking at least 50V higher and PV amps dropping to near 0 at 13:45.

This is the same issue I am having with 12k. And yet I am told by Sol-Ark that I am the only one with this problem. The issue with the spikes is that even though Voc is OK per sol-ark string calculator, I have seen spikes that go over their max input of 500V and over the Voc of the array. This can damage the inverter.
So, Clint, even if you are OK with the limit of 13k watts on the inverter, you still have this other problem.
Like in my previous post, I wonder if this issue is more common and not being seen by sol-ark owners because they don't know it's a problem. It may be a hardware or software design flaw affecting many if not all Sol-Ark products.
The warranty period on the Sol-Ark is a long time and you people who are happy now with your inverter, that's great. But what happens when the inverter fails? Will Sol-Ark be able to fulfill their warranty obligations? They have not solved my problem nor Clint's. These are fair questions. It's a yes or no answer with no need to go into where the sol-ark came from, who designed it, where it's made or what color the sky is.

 

[Clint-L]

In your chart at the time you have marked with the cursor - 13:45, PV is producing 63 watts while microinverters are at 1799watts. So it looks like at this point the DC PV input to the inverter is producing almost nothing while the microinverters are continuing to produce.
How many watts of panels are now wired to the microinverters?
I'd like to see a chart of your Sol-Ark PV volts and amps for the same time period as that chart. I think we would see PV volts spiking at least 50V higher and PV amps dropping to near 0 at 13:45.

This is the same issue I am having with 12k. And yet I am told by Sol-Ark that I am the only one with this problem. The issue with the spikes is that even though Voc is OK per sol-ark string calculator, I have seen spikes that go over their max input of 500V and over the Voc of the array. This can damage the inverter.
So, Clint, even if you are OK with the limit of 13k watts on the inverter, you still have this other problem.
Like in my previous post, I wonder if this issue is more common and not being seen by sol-ark owners because they don't know it's a problem. It may be a hardware or software design flaw affecting many if not all Sol-Ark products.
The warranty period on the Sol-Ark is a long time and you people who are happy now with your inverter, that's great. But what happens when the inverter fails? Will Sol-Ark be able to fulfill their warranty obligations? They have not solved my problem nor Clint's. These are fair questions. It's a yes or no answer with no need to go into where the sol-ark came from, who designed it, where it's made or what color the sky is.

Here’s it doing the same thing today. Same exact thing yes. Check it out.

Note - Array one is a max of 5,120w because I pulled 2kw out of it and put micro inverters in them. Micro max power is about 1910w. When the DC PV drops, the micros are remaining fine. It’s like a throttle/reset occurring on the MPPT’s and then it stabilizes after doing this a couple times once full sun is in effect. The stabilization point is at about 13.2kw.

The other two arrays are both 6,400w each max.

 

[Solar Guppy]

I read through the entire thread again trying to see clues to what may be causing / triggering this behavior

From other 15k users, they can sell 15k of solar through the inverter, and the OP has two units that do the same thing so it must be site specific trigger.

There is some type of event being triggered at the point of throttling back to the 13K limit

One thing I was not sure of was where the adding of micro inverters ( which allows full solar harvest ) is separate circuit to the main panel?

In the images, I keeping seeing the grid port is on the high side, running at 248V ( can the grid profile be modified to up the UL1741SA defined thresholds? )

I've been out of GT inverter designs for a while but did some reading on the changes for UL1741-SA and came across a feature that would do exactly what is seen by the OP. This is shown on page 9: 3.3 Autonomous Volt-Watt Operation

This is a feature to have inverters automatically help stabilize the grid, as the grid voltage increases, there are define regions the units will self reduce power output as a percentage of the defined maximum. I would look at the grid profile and see where this starts to be engaged and if you can change them temporally to see if it resolves the issue.

If you can add a load at the grid port, like a water heater or other large load, that would bring down the voltage for a test to see if the solar can export the full 15K

 

[Clint-L]

You have some good points. I’ve wondered a bit about the voltage on grid getting too high. I have tried running some heavy loads to use most of the PV power and it didn’t seem to help. I still question your point though because without any Solar, I always have 122.3 volts on L1/L2.

This problem persisted before I added the micros. I added micros because I wanted to harvest some of the power in loosing. So I started with three arrays that were 6.4kw each. Now I’ve peeled off some panels and one of the arrays is only 5.1kw.

It’s interesting that the moment before I’ll get a DC PV drop out, I’ll see more amperage / power on the arrays. Then, boom it’s basically resets the MPPTs and ramps back up. They always like to stabilize at about the same amperage of 15amp~ each when they are seeming to clip. If I pull one array out, doesn’t matter which, I’ll see the other two produce 18 to 20amps each at around 6.1kw~.

This is today. It was mostly clear but we had a few clouds pass and you can see on the micros that they will match. But you can also see one of those dips where the MPPTs reset.


PV number 1 is the array that’s a little smaller now at about 5,120w max. It’s two strings of 8 in series paralleled.


Here’s a zoom in on just the voltage at 10:56am. This seems to happen if we have a cloud maybe then the sun pops out and it is like it just has an overload moment. So strange.

 

[Solar Guppy]

This is a site issue, and the cause could be a momentary rise in the grid voltage as seen by the inverter as it is the source, not load triggering as UL1741-SA power reduction as I linked in the previous post.

Your graph above are DC values, I'm discussing AC values as the trigger. We don't need to prove the mppts are the cause, they are just how the inverter throttle the harvest. There maybe a separate issue of how the unit handles edge of cloud events, ( the zeroing and resuming of power delivery ) but one issue at a time

While turning on loads some where else could help, it may not if the issue is rise in voltage as the inverter sees it with wiring from the inverter to the main panel.

Get yourself a DVM that has peak hold function, this will see detect and hold the reading. Here is one on amazon the might do the job, but you can search using digital multimeter hold as the key words.

Adding a large load, at the inverter on the grid port itself should be the next test and or having a peak hold to measure the AC voltage. The data logging you have just points to the direction, 5 minute logging can't do a smoking gun on issues like this.

 

[629658]

I’m not sure this has anything to do with it but in some of your attachments I see your load curves all “spikey” and not relatively smooth. This is not how mine appears at all. Not sure why but definitely different than mine. I have load spikes but they are relatively smooth. Probably nothing to do with it but it is definitely different

 

[SolarRich]

Clint - do you have batteries connected? In closed loop or open loop? When my batteries batteries are in closed loop is when I get the drops and spikes. In open loop all is well.
Solar Guppy - In my case I asked Carlos at Sol-Ark about monitoring the AC power. That I could hook up a scope that records. His response was that the AC side is not where the problem is. It was after this he determined that the battery closed loop communication had something to do with it.
jfpetesn - Wow, it's good to see how these graphs are supposed to look.Do you have batteries?

Perhaps these drops and spikes can have multiple causes? Either a short duration event on the AC or the Sol-Ark responding incorecctly to a battery event. Or a battery event that should not happen and the sol-ark is responding correctly?

Clint took some power off the DC side by using microinverters. For a couple months I took one 400w panel out of each of the 2 PV strings. During this time the drops and spikes were significantly reduced. While the batteries were in closed loop mode.

 

[629658]

Clint - do you have batteries connected? In closed loop or open loop? When my batteries batteries are in closed loop is when I get the drops and spikes. In open loop all is well.
Solar Guppy - In my case I asked Carlos at Sol-Ark about monitoring the AC power. That I could hook up a scope that records. His response was that the AC side is not where the problem is. It was after this he determined that the battery closed loop communication had something to do with it.
jfpetesn - Wow, it's good to see how these graphs are supposed to look.Do you have batteries?

Perhaps these drops and spikes can have multiple causes? Either a short duration event on the AC or the Sol-Ark responding incorecctly to a battery event. Or a battery event that should not happen and the sol-ark is responding correctly?

Clint took some power off the DC side by using microinverters. For a couple months I took one 400w panel out of each of the 2 PV strings. During this time the drops and spikes were significantly reduced. While the batteries were in closed loop mode.

Yes I am running 928 aH of Trophy batteries open loop and 13.4 kW of DC coupled array.

 

[Clint-L]

I’m now running EG4-LL stack of 6 of them and a total of 609ah. Interesting about the closed loop. We did some testing around it with solark a while back and couldn’t find an issue. We set them up as lead acid etc.

Also, when I first got the original 15k I had an old lead acid battery bank and was seeing this issue as well.

Today, I disabled grid charge, which I like to have because I do take advantage of TOU during peak utility grid charge times to supplement my load and then charge back with cheap power at night. The only reason is, so if I had a power outage early in the morning I don’t want to have dead batteries. That would really suck after dumping so much cash. lol ?

We are having a cloud/storm system here in Oklahoma for the next few days so I won’t be able to get much useful data until this moves out. But I’m curious about maybe letting my batteries pull a healthy load like was suggested earlier in thread. That would be great, even though just selling back to the grid would be better!

One last thing. My grid voltage usually stays at the following:

At rest - no PV production
L1- 122.0
L2- 122.5

Moderate PV production
L1- 123.8
L2- 124.0

A few times a day spiking during full PC production and system throttling out at 13.2~kw
L1- 125.4
L2- 125.3

 

[robby]

Mine is either at 118-120V per leg When under normal load or may dip slightly under a heavy load.

It would be interesting to hear what other 15k owners are seeing.

 

[Solar Guppy]

One last thing. My grid voltage usually stays at the following:

At rest - no PV production
L1- 122.0
L2- 122.5

Moderate PV production
L1- 123.8
L2- 124.0

A few times a day spiking during full PC production and system throttling out at 13.2~kw
L1- 125.4
L2- 125.3

That's an issue, those values indicate a resistance of .103 ohms ( rise of 6.2V Volts @ 60 amps ). That's really high.

You need to find where the line rise is located from the inverter to the utility meter ( 251 is very close to the typical 254 trigger point in some UL1741 parameters ). Since this is a UL1741-SA Inverter there is automatic derating also based of active and reactive AC power.

Start at the main breaker and work towards the inverter with the voltage measurements, you will likely find a point that shows the most voltage increase.

Can you describe the wiring from the utility connection to the inverter?

 

[2TrevorJ]

My grid power has always been high at ~249-253V (even before my solar install).

With 2x15K's on 28 Jan:

At rest - no PV production
L1- 125.0
L2- 124.7

Highest sample during PV production (13 kW production w/ 10.6 kW export)
L1- 126.6
L2- 126.7

No alarms or even dark shaded measurements on the Master's details screen. Running the default grid setup so UL1741-SA and high voltage faults start at 263.8V.

 

[Solar Guppy]

My grid power has always been high at ~249-253V (even before my solar install).

With 2x15K's on 28 Jan:

At rest - no PV production
L1- 125.0
L2- 124.7

Highest sample during PV production (13 kW production w/ 10.6 kW export)
L1- 126.6
L2- 126.7

No alarms or even dark shaded measurements on the Master's details screen. Running the default grid setup so UL1741-SA and high voltage faults start at 263.8V.

UL1741 SA has auto derating of maximum power to grid ( on active and reactive power each with different trip points ) before the high voltage trip values, that's what I am thinking about here.

We have two sites, both running high line side AC voltage that both are throttling Maximum PV harvest to grid.

One test would be if the unit allows different grid profiles such as just UL1741 ( not SA ) and see if it resolves the issue.

 

[2TrevorJ]

We have two sites, both running high line side AC voltage that both are throttling Maximum PV harvest to grid.

Oh no no no...I had home loads and charging going on that ate up the missing 2.4 kW. I don't believe it was throttling judging by the PV curve and the intermittent clouds that were rolling by that day. The earlier peak was 17.3 kW of production but of course that's two 15K's combined and a 20.4 kW array (total). Output/Grid Voltage during that time was L1-125.8 L2-126.0.

I just posted to add data to the high(er) grid voltage behavior/rise.

 

[629658]

L1 122.3
L2 123.2
PV production 3750 watts, cloudy, loads 4500 watts.

 

[Clint-L]

Question - if it was related to grid voltage would that mean that the upper PV production limit would be limited based on what that voltage was? I’m not seeing any correlation on that. Here’s a graph with PV and L1/L2 voltage. Thoughts?

 

[Solar Guppy]

It is clear, when you AC grid voltage rises, the clipping starts, I put pointers and a box on your photo

You have an issue on your site voltage, you are having a 6-7 volt rise on the grid port, when it should be more like 1 to 2 volts at most.

I've written this numerous times, you need to find out from the inverter to the main breaker WHY you have this much voltage rise, it is NOT normal

Can you please detail the path from the inverter grid port to the main breaker panel, wire gauges and lengths.

 

[Spunky]

you need to find out from the inverter to the main breaker WHY you have this much voltage rise, it is NOT normal

The problem may be outside.

Do you know what kva transformer the electric company has feeding our system?
I'd guess you'd have at least a 25kva, a 50kva may be needed.

 

[Spunky]

Hopefully it's well marked like this one,but not leaking oil.