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My SolArk 12k install with Enphase Micros

Ampster

Renewable Energy Hobbyist
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May 3, 2020
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Location
Kenwood, California
I had previously reported on my Outback Skybox install with a 7kW Enphase micro GT system..

I recently evaluated my needs and the easiest way for me to add incremental capacity is with micros on my west facing roof pitches. For a couple of reasons I decided to upgrade to a SolArk 12k which in reality is only a 9kW inverter. However inverter capacity is not my my need. What I need is more charging capacity for my 42 kWh pack and more AC coupling capacity. The SolArk met those needs and I found a local supplier where I could will call an inverter with no freight charges.
Removing the Skybox was a challenge because it weighes almost 100 lbs but I got it done in half a day and got the SolArk mounted in a few hours. I hooked up the SolArk temporarily so I could charge my battery pack.

Because the SolArk has an option to use the Generator in port for my AC coupled micros that will simplify my connection and free up some breaker spaces on my critical loads panel. I am going to add a small sub panel where my micro circuits come into my building and run a 50 Amp leg direct to the Generator input on the SolArk.

This is a work in progress and I will update as phases get completed.

In the meantime my Skybox is listed at $1800 here:
 
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The skybox is nice for someone that wants a simple and clean setup for backing up a critical loads panel.
 
I got the SolArk installed and my micros going through the Gen port. Still trying to figure out if there is a way to force it to do a full charge from the grid so I can reset my battery to 100%. The battery is reading 100% now but only at 52 volts. or 3.25 per cell and the charging rate is only 1kW but it is selling 3kW to the grid. I unchecked TOU thinking that would help but maybe not..
 
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Curious if you are using BMS comms or just voltage base. If voltage base, do you have to calibrate and compensate for losses and drops.
 
On another note, do you have any tips for commissioning your own enphase system? I got ahold of 20 iq7+ and panels.
 
Curious if you are using BMS comms or just voltage base. If voltage base, do you have to calibrate and compensate for losses and drops.
I have not started on the BMS communication. I want to understand the basics first. It is a totally different approach than what I was used to with the Skybox. There was actually a button to reset SOC which started a grid charging cycle. I am missing that simple step.
Until I get the battery fully charged I am using voltage. So far it tracks with my BMS. I have not yet compared that to my VOM
On another note, do you have any tips for commissioning your own enphase system? I got ahold of 20 iq7+ and panels.
I was lucky several years ago and got an installer account. Other members here have taken the course so they have access to the commissioning process. I wish I could give you some tips on the mapping interface. My two arrays look nothing at all like the physical map.
 
My brother wants to add storage, your old SkyBox would be perfect. He has a 4KW SunPower grid tied system now. Not sure he wants to drive up there to pick it up, but that would still probably be less than shipping it. I'll ask if he is interested.

I'll b following this thread. The Sol-Ark has a great feature set, but I am curious how well it does the time of use for you. Is it close to what 400bird and I are able to do with our aftermarket controlled XWs.
 
Not sure he wants to drive up there to pick it up, but that would still probably be less than shipping it. I'll ask if he is interested.
I make several trips to Hermosa Beach every year and would consider delivering it during one of those trips, assuming he is somewhere in the basin. Of course I could always drop it off at your place as well.

I am having some maintenance done on an Apartment I own in Hermosa Beach and I might have to make a trip in January.
The Sol-Ark has a great feature set, but I am curious how well it does the time of use for you.
I am anxious to see myself. That was a feature set that was one of my decision drivers. Since then I have discovered that it also has seasonal inputs which could fit my needs since my loads are more in winter. My goal would be to fall back to grid charging in winter during off peak. During summer my loads are less so I could be in self sufficient mode all summer long and totally avoid that $0.55 /kWh peak rate.

Initially I started out with my pack at 60 percent and because did not have the settings correct it drained my battery overnight. SolArk support was very helpful and responded within hours. It is now charging from the grid and from available solar at 7kWs. I used a conservative CV setting until I calibrate the SolArk, my BMS and my Fluke. Initially the SolArk is about 0.2 volt high which is better since it will give me some cushion. My Skybox was about the same so a setting of 3.45 volts per cell would equate to 55.2 volts for a CV.
 
I talked with my brother, he is not quite ready to jump in, so he is opting out of your Skybox. I am sure you won't have trouble finding a buyer at your price.
 
I heard back from SolArk Support regarding the TOU settings. He explained that the TOU settings need to be in chronological order, which makes sence. I also suspect but he did not mention it but any changes do not take affect until the next time period. In other words if you enable TOU at 9:30 and one of your settings starts at 9:00 you won't see the effect of that setting until the next time the clock circles past 9:00, which would be the next day. Earlier the tech had me cycle down and cycle up the system and I suspect that is one way to implement a change immediately. Here are the three things he explained to me:

  • If no grid charge boxes are enabled, it will discharge the batteries until the Batt setting is reached. In this case, PV will always charge the battery. Also, if you would like to charge the batteries just from PV, you just have the set 100% during the time slot you want to.
  • When the charge boxes are enabled, the inverter will charge the battery from an AC source (Grid, Generator, or AC coupled input) connected to the Sol-Ark inverter at a specified time block until the Batt setting is reached. Batteries will charge from the grid first if it's available.
  • The "Sell "box" will allow the inverter to discharge the battery and push battery power back to the Grid breaker or the grid at the rate of the Power(W) setting until Batt setting is met.
Here is an example he sent me:

1671671587554.png
 
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i checked the system this morning and it is behaving like i wanted. At 10AM it is cloudy out, so very little solar., It is off peak TOU time and the house is running on the grid and the batteries are at 100 percent. As programmed, the batteries charged back up to 100 percent at 3AM,shich is how I programmed the TOU settings for winter. They had supported the loads during the peak times from 3PM to 10PM. I do not have complete confidence in the SOC settings yet and will have to verify with my BMS how the SolArk is tracking SOC vs, the BMS.

In summer I will let the batteries carry the house loads until the batteries can charge from solar during the day.
 
Are you finding that the Sol-Ark is functioning as expected now?

Is the functionality pretty equivalent to the Outback Skybox?
 
I am not sure I understand or have confidence in the SOC percentages as variables for the TOU settings in the SolArk. I have been through a couple of 24 hours cycles and have seen the SolArk charging my battery from the grid during peak times. I have several choices. I could just uncheck the Charge box during those times and or I could just go to voltage as the criteria.
As I ponder this, I do not want to change too many variables so I think I will just uncheck the charge boxes during peak times in which I have the battery draw during those times maxed at 2k. What I have defined as peak hours is only seven hours from 3PM until 10PM. Worse case it woul take my pack to 66%SOC at 10PM.
I am beginning to understand how the programming works and like the flexibility it gives me. Tomorrow I get the Solar Assistant Raspberry PI which I ordered from Watts247.
 
The program I created in my PLC is very basic. It works find when solar production is good, but when I have 2 bad production days in a row, it goes stupid on me. If nothing else, I need to program in a simple override. What I did today was just unplug the PLC and set a fixed charge current for3 hours to get the battery back up to a decent state of charge again. My Enphase panels made 10 KWH today, but I pushed 10.4 KWHs into the battery, Oops. I was trying to keep that even, but I was a little late in dialing it back. I was hoping for a bit more sun, as well, but we had clouds move back in again, cutting solar production to less than half at 2:15 pm. But I still have the XW-Pro set to block charging at 4 pm, so it only used the cheap time of use power to charge. Under my current rate plan, the grid power I used was at 24 cents. After 4 pm it went up to 38 cents. You're not going to get rich making a 14 cent per KWH profit.

When you get the Sol-Ark fully dialed in, I would be very curious to see your battery SoC trace and the grid power trace for a few days. If I get at least 13 KWH from my solar panels, my system does really well, keeping the grid very close to zero all day. But when production is too low, It does not ration the power well yet.

One thing I was going to "fix", but I actually like now, is how it handles the charge current control before 4 pm when there is load in the main panel. If solar production is weak, and loads in the house, are high, it treats the backup loads panel different from the main panel. This was my easy way of ensuring I only charge the battery from PV Solar power. If the power in the backup loads panel drops below zero, it will stop charging, and by default, the XW will start powering loads in the backup panel. But, loads in my main panel before 4 pm will not stop the battery from charging. As long as the backup panel load is being covered by the solar power, it will keep charging, even if I am drawing 5,000 watts from the grid back in the main panel. It just lowers the charge current to 5% (7 amps), but it keeps charging. I know that all that power has to be coming from solar because the power in the backup panels has not gone negative. And since I know I have at least 400 watts pulling from the backup panel at all times, charging the battery at 400 watts is less than solar production. It's not perfect, but it reduces my chances of running out of battery too soon.

What I want to add is a way to force it to put some extra into the battery during the cheap rate time so I can always cover the high rate time block. I am not doing any statistics in the PLC yet, but if I average the KWHs used from 4pm to 9pm each day, I should be able to force some charging to ensure I have that much energy available in the battery each day before 4 pm. It does not need to be very smart, I just need to have my current battery over 53.5 volts by 4 pm, and I know it will make it past 9 pm on days I don't need the A/C. In the summer when I need the A/C a lot, I may also just set it to stop exporting to the main panel overnight. If the A/C has to run at 3 am, let it use the cheapest rate grid power.
 
When you get the Sol-Ark fully dialed in, I would be very curious to see your battery SoC trace and the grid power trace for a few days. If I get at least 13 KWH from my solar panels, my system does really well, keeping the grid very close to zero all day. But when production is too low, It does not ration the power well yet.
I will try to remember to do that. I am hoping Solar Assistant will allow me to do that. Also @robby just posted about a new interface so that may also help. It is good I made the purchase now because the winter is the challenging time because loads are high and production is often down. It just started rainingba few hours ago and you will probably see it in the morning.
 
I had previously reported on my Outback Skybox install with a 7kW Enphase micro GT system..

I recently evaluated my needs and the easiest way for me to add incremental capacity is with micros on my west facing roof pitches. For a couple of reasons I decided to upgrade to a SolArk 12k which in reality is only a 9kW inverter. However inverter capacity is not my my need. What I need is more charging capacity for my 42 kWh pack and more AC coupling capacity. The SolArk met those needs and I found a local supplier where I could will call an inverter with no freight charges.
Removing the Skybox was a challenge because it weighes almost 100 lbs but I got it done in half a day and got the SolArk mounted in a few hours. I hooked up the SolArk temporarily so I could charge my battery pack.

Because the SolArk has an option to use the Generator in port for my AC coupled micros that will simplify my connection and free up some breaker spaces on my critical loads panel. I am going to add a small sub panel where my micro circuits come into my building and run a 50 Amp leg direct to the Generator input on the SolArk.

This is a work in progress and I will update as phases get completed.

In the meantime my Skybox is listed at $1800 here:
At $1800 it’s a no brainer for someone to buy it versus the new EG4 unit.
 
BTW what mode are you guys in? Loads First or Battery First?
 
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