I installed 30 295 watt panels with 30 enphase IQ 6+ micros on my house back in 2017. I am an industrial electrician, and this was all new to me. It was fun to learn about and plan and install. I'm wondering the most economical way to safely setup a Hybrid Inverter of some kind that will create the frequency my IQ6's need to generate power, but also keep a small backup battery unit charged up. Is there a way to utilize the up to 60amps my panels are making during the day, in an emergency, to run AC and Fridges etc, but a sunset and power loss have the batteries provide enough for lighting and phone charging etc. I don't care to go off grid at this point. I just want a low cost option to create an emergency back up plan. I also have a 4500 watt generator I want to be able to run as needed tied into the system. I plan to make some kind of wall pack from 18650's or the like, and with my panels outputting 240v AC already, the battery wall pack can be set up at any voltage for charging/inverting whatever... I've watched many many videos, but could use input and advice into my idea, as I haven't really seen anyone doing this that already has Micros in the system. Thanks mates
Enphase AC to hybrid system
- Thread starter amanra13
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GXMnow
Solar Wizard
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You probably have heard about the new Enphase Ensemble system. There is a write up of one on here.
diysolarforum.com
The Ensemble looks like a great system, and I had looked into it, but they kept delaying the announcements. I finally gave up and decided to do my own thing. It sounds like you are more of a "roll your own" kind of guy as well, so take a look at my thread in the "Show and Tell section"
diysolarforum.com
I have a smaller Enphase setup using 16 iQ7's with 300 watt panels. I am doing an AC coupled setup with a Schneider XW-Pro battery based inverter. My battery bank is built from 3 of the modules out of a Chevy Bolt EV. You could use a crap load of 18650's, and that was one of my early thoughts, but to get enough storage it becomes a huge number of connections to deal with. Check out Battery Hookup. They are out of the Bolt packs I used, but they do have a great deal on a comlpete battery setup out of a BWM. Even with the truck freight shipping, the cost per KWH is very good. If I was going to build up a pack again, I might go with some of the better made Chinese aluminum cased LiFePo4 cells. I was also close to buying 32 150 amp hour cells, but the Bolt packs came in at half the price, so I got lucky. Nissan Leaf modules are also a good source, but the used ones on the market are only giving about 75% of their rated capacity. Not sure how much longer they will last.
The iQ6+ inverters have a maximum continuous output of 280 watts. Are you on household 120/240 split phase in the US, or on 120/208 3 phase, or in a 230 volt market? I will assume 120/240 for now as that is what I have here. Your existing 30 x 295 watt panels should be wired to 240 volt line to line if you are here in the US. Each inverter then outputs a maximum of 1.17 amps at 240 volts. 30 of them will top out at 35 amps. Due to the trunk cable being #12 awg, it should be split into at least 2 banks. The total solar power to your AC panel could peak up to 8,400 watts. That is a bit too much to put on one XW-Pro inverter like I have. They recommend not exceeding the inverter's maximum continuous current. That is just 6800 watts. So you could keep up to 24 panels on a single XW-Pro. Any current that the solar inverters produce, needs to be able to flow back into the inverter.
I am having one issue right now, and that is trying to force the XW-Pro inverter to charge my battery fully when the sun is over powering my home, and then force it to use the battery to push that power back out during the high 4 pm to 9 pm peak rate time each night. If you are only using the battery for backup power, this flaw is not an issue at all. When the grid power goes out, the XW-Pro inverter will open it's grid input contactor, and the inverter will continue to create a clean 120/240 split phase sine wave output. The change over time is about 8 milliseconds, so most devices will not react and just go on working. About half of my Enphase array did drop offline last time I tested a simulated power failure. Enphase is looking into why it happened. All of the loads that you want to be able to run during a power failure need to be moved into an "Essential Loads" breaker panel which will now be powered by the output of the battery based inverter. Whether it is a Schneider like mine, and Outback Skybox, an SMA Sunny Island, a Sol-Ark, or a Tesla Power Wall 2, they all have to disconnect from the grid like that. In your case, 6 of your Enphase micros should stay in the main panel, and they will stop working during a power failure. If you can move around the trunk cable, choose the 6 with the lowest production, put the best 24 panels in the "Essential Loads" breaker panel. Since I have just 16 panels, I have the entire Envoy Combiner 3 connected to my "Essential Loads" panel. The Skybox can take up to 7,600 watts of solar, not sure about the others.
With the inverter powering your important loads, the Enphase micros still see a good "Grid" and they should keep producing, or if they did glitch, they should re-connect after 5 minutes. The solar power helps power your loads. If the solar start to produce more power than you are using with your important loads, any extra power does go into the inverter's output. It will actually reverse function and use that extra power to charge the batteries. Different inverts act a little different from here, but there is one common function. Once the battery inverter sees there is to much power coming in, it only has one way of adjusting the power that is coming from the grid tie solar inverter(s). That is to shift the AC line frequency up above 60 hz. If your inverters are running an older grid code, they will keep producing power until the frequency goes too far out. Sometime before 62.5 Hz, most inverters will just shut off. Then you run back on just battery for 5 minutes until the inverter(s) re connect. If your iQ6+'s have been updated to support "Frequency / Watt control" they should be able to ramp down their output as the frequency increases. The battery inverter could be forced to do this for two reasons. Most of them will do it when the battery is fully charged. Many of the older units like the earlier Schneider XW+ before the Pro version, could not actually regulate the charge current and you would have to ensure your batter bank could handle the full power, until the batteries reached the absorb voltage. The XW-Pro and the Skybox can both shift the frequency any time during off grid charging to regulate the charge current based on the charger settings. So now you should have solar running all that you need, and your battery is topped off. The local fake grid may be running at 61 .5 hz, but other than that, all is well. As the sun goes down, the solar output will fall to where it can't keep up with the loads. At that point, the box switches from charging to inverting and now the battery is powering everything in the backed up panel.
If the battery is sized well and you had a good charge in the battery before the blackout, the battery should be able to run your home through the night, and once the sun comes up, it will start charging things back up from the solar again.
The one bad thing if all of your solar is AC coupled is that if the battery does run down to the Low Battery Cut Off point, the inverter will turn off and you no longer have the fake local grid. This is bad because, now the sun can't recharge the system, because the micro inverters on the roof do not see a grid again. There are a few solutions. The best is to ensure you don't run the batteries that low. Some do it manually by switching off things they don't need. Some add a "load shed" relay that can turn off a few less important things when the battery voltage is getting low, but still has enough power to keep the sine wave flowing to kick off the solar again in the morning. And another option is to have an auto start generator that can give the battery bank a kick when the battery goes too low.
After you read this and go over my thread, feel free to ask any questions.
An Enphase Ensemble Installation
Panels are up, final inspection today hopefully and net-meter should get installed soon. Still about a month away from the batteries. I'll start blogging in this thread all the stuff I learn and a full description of the system as I have time. If there are specific questions you have just...
diysolarforum.com
The Ensemble looks like a great system, and I had looked into it, but they kept delaying the announcements. I finally gave up and decided to do my own thing. It sounds like you are more of a "roll your own" kind of guy as well, so take a look at my thread in the "Show and Tell section"
Adding storage to my Enphase system
I am still fairly new on the forum, tried to answer a few questions as I asked some, and have been talking about my plans and purchases. I figure this is the right place to talk about what I am doing and where it is going. My existing system is a very typical Enphase setup. I have 2 arrays of 8...
diysolarforum.com
I have a smaller Enphase setup using 16 iQ7's with 300 watt panels. I am doing an AC coupled setup with a Schneider XW-Pro battery based inverter. My battery bank is built from 3 of the modules out of a Chevy Bolt EV. You could use a crap load of 18650's, and that was one of my early thoughts, but to get enough storage it becomes a huge number of connections to deal with. Check out Battery Hookup. They are out of the Bolt packs I used, but they do have a great deal on a comlpete battery setup out of a BWM. Even with the truck freight shipping, the cost per KWH is very good. If I was going to build up a pack again, I might go with some of the better made Chinese aluminum cased LiFePo4 cells. I was also close to buying 32 150 amp hour cells, but the Bolt packs came in at half the price, so I got lucky. Nissan Leaf modules are also a good source, but the used ones on the market are only giving about 75% of their rated capacity. Not sure how much longer they will last.
The iQ6+ inverters have a maximum continuous output of 280 watts. Are you on household 120/240 split phase in the US, or on 120/208 3 phase, or in a 230 volt market? I will assume 120/240 for now as that is what I have here. Your existing 30 x 295 watt panels should be wired to 240 volt line to line if you are here in the US. Each inverter then outputs a maximum of 1.17 amps at 240 volts. 30 of them will top out at 35 amps. Due to the trunk cable being #12 awg, it should be split into at least 2 banks. The total solar power to your AC panel could peak up to 8,400 watts. That is a bit too much to put on one XW-Pro inverter like I have. They recommend not exceeding the inverter's maximum continuous current. That is just 6800 watts. So you could keep up to 24 panels on a single XW-Pro. Any current that the solar inverters produce, needs to be able to flow back into the inverter.
I am having one issue right now, and that is trying to force the XW-Pro inverter to charge my battery fully when the sun is over powering my home, and then force it to use the battery to push that power back out during the high 4 pm to 9 pm peak rate time each night. If you are only using the battery for backup power, this flaw is not an issue at all. When the grid power goes out, the XW-Pro inverter will open it's grid input contactor, and the inverter will continue to create a clean 120/240 split phase sine wave output. The change over time is about 8 milliseconds, so most devices will not react and just go on working. About half of my Enphase array did drop offline last time I tested a simulated power failure. Enphase is looking into why it happened. All of the loads that you want to be able to run during a power failure need to be moved into an "Essential Loads" breaker panel which will now be powered by the output of the battery based inverter. Whether it is a Schneider like mine, and Outback Skybox, an SMA Sunny Island, a Sol-Ark, or a Tesla Power Wall 2, they all have to disconnect from the grid like that. In your case, 6 of your Enphase micros should stay in the main panel, and they will stop working during a power failure. If you can move around the trunk cable, choose the 6 with the lowest production, put the best 24 panels in the "Essential Loads" breaker panel. Since I have just 16 panels, I have the entire Envoy Combiner 3 connected to my "Essential Loads" panel. The Skybox can take up to 7,600 watts of solar, not sure about the others.
With the inverter powering your important loads, the Enphase micros still see a good "Grid" and they should keep producing, or if they did glitch, they should re-connect after 5 minutes. The solar power helps power your loads. If the solar start to produce more power than you are using with your important loads, any extra power does go into the inverter's output. It will actually reverse function and use that extra power to charge the batteries. Different inverts act a little different from here, but there is one common function. Once the battery inverter sees there is to much power coming in, it only has one way of adjusting the power that is coming from the grid tie solar inverter(s). That is to shift the AC line frequency up above 60 hz. If your inverters are running an older grid code, they will keep producing power until the frequency goes too far out. Sometime before 62.5 Hz, most inverters will just shut off. Then you run back on just battery for 5 minutes until the inverter(s) re connect. If your iQ6+'s have been updated to support "Frequency / Watt control" they should be able to ramp down their output as the frequency increases. The battery inverter could be forced to do this for two reasons. Most of them will do it when the battery is fully charged. Many of the older units like the earlier Schneider XW+ before the Pro version, could not actually regulate the charge current and you would have to ensure your batter bank could handle the full power, until the batteries reached the absorb voltage. The XW-Pro and the Skybox can both shift the frequency any time during off grid charging to regulate the charge current based on the charger settings. So now you should have solar running all that you need, and your battery is topped off. The local fake grid may be running at 61 .5 hz, but other than that, all is well. As the sun goes down, the solar output will fall to where it can't keep up with the loads. At that point, the box switches from charging to inverting and now the battery is powering everything in the backed up panel.
If the battery is sized well and you had a good charge in the battery before the blackout, the battery should be able to run your home through the night, and once the sun comes up, it will start charging things back up from the solar again.
The one bad thing if all of your solar is AC coupled is that if the battery does run down to the Low Battery Cut Off point, the inverter will turn off and you no longer have the fake local grid. This is bad because, now the sun can't recharge the system, because the micro inverters on the roof do not see a grid again. There are a few solutions. The best is to ensure you don't run the batteries that low. Some do it manually by switching off things they don't need. Some add a "load shed" relay that can turn off a few less important things when the battery voltage is getting low, but still has enough power to keep the sine wave flowing to kick off the solar again in the morning. And another option is to have an auto start generator that can give the battery bank a kick when the battery goes too low.
After you read this and go over my thread, feel free to ask any questions.
Can you provide the model of 240v inverter you are using tied to your batteries? I have a similar setup I'm trying to design for and only have (6) 320w panels today. I just want to create a fake grid so that my panels work but also have the batteries as emergency power instead of UPS devices everywhere which need new batteries every few years. I lose power a lot in my area.
GXMnow
Solar Wizard
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- Jul 17, 2020
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My system is using a Schneider XW-Pro inverter/charger and an 18 KWH Li NMC battery bank.
For backup purposes, it works great. I have 16 300 watt panels with Enphase iQ7 inverters. When I did my first power fail simulation, About half of the iQ7's did drop out. This seems to have been caused by 2 things. The main one being that the California Rule 21 settings in the iQ7's is pretty picky about the line frequency bump as the system switches over. It should go back online after 5 minutes, but they didn't. Once the sun went down and back up, it did all come back to life. I was also able to cover a panel and it came back when I uncovered it again. It seems this happened because there was very little load in my backup loads panel. So there was quite a spike when the load from the main panel went away. I put 1,000 watts of load in the backup panel and did it again, and only one panel shut down when I tripped the main. That was a much better result. Once in backup mode, it all worked perfect. Even down a few panels that first time, the remaining solar was enough to supply all the loads, and the XW-Pro was using all of the excess power to charge the battery bank. As the sun went down, it seamlessly reduced the charge current and then started using battery power to supply the loads. The Enphase software only reported the error of the panels that had shut down. Enphase is working on a software update as they have seen the same thing happen with Tesla Powerwall2 installations. I think it won't be a problem at all if I have more load on the system, or if the sun is down when the power fails. In every case, when the sun comes up, all panels work perfectly. It has only been an issue when the solar was producing more power than my load when the power cut.
I have found an odd problem in the Schneider software that does cause one issue though. I also want to time shift some power from when there is excess solar to the evening 4PM to 9PM peak "Time of Use" rate. So I have it programmed to top up the battery from 9AM to 4PM, and then switch to grid support and help power my home from 4PM to 9PM. But the grid support always stops producing power 0.5 volts above the point where the battery voltage will trigger a recharge. But then it won't charge, because the battery is still above the recharge voltage setting. It is a very stupid error in the program, but Schneider does not seem to care. It does not hurt the backup power mode at all, it is only an issue with the grid being up. Their "Fix" is to use DC coupled solar to provide the charge. That is certainly not practical as a retrofit to a micro inverter system. I hope they will issue a software patch for AC coupled, but so far they have not. My data has been sent to their engineers, or at least they said it was.
My "fix" is a work in progress. I have it narrowed down to only having to change the value of 2 numbers in the settings 2 times a day. I am programming a micro controller to send the commands. I am just working out the timing now. It seems the responses from the XW-Pro inverter are quite slow and my software is not waiting long enough for the replies. I hope to have it all worked out soon. The XW-Pro inverter is a great piece of hardware and has no issues cranking out far more power than I will ever need. My only issue is this power time shifting to save a few bucks on my electric bill to try to offset some of the cost. I have been manually changing the values most days, and I have been able to shave off nearly $2 a day on average with the time shifting. That comes out to nearly $700 a year. So I want to make it work. And if I can get So Cal Edison to move me to the Prime D rate, I will save even more.
For backup purposes, it works great. I have 16 300 watt panels with Enphase iQ7 inverters. When I did my first power fail simulation, About half of the iQ7's did drop out. This seems to have been caused by 2 things. The main one being that the California Rule 21 settings in the iQ7's is pretty picky about the line frequency bump as the system switches over. It should go back online after 5 minutes, but they didn't. Once the sun went down and back up, it did all come back to life. I was also able to cover a panel and it came back when I uncovered it again. It seems this happened because there was very little load in my backup loads panel. So there was quite a spike when the load from the main panel went away. I put 1,000 watts of load in the backup panel and did it again, and only one panel shut down when I tripped the main. That was a much better result. Once in backup mode, it all worked perfect. Even down a few panels that first time, the remaining solar was enough to supply all the loads, and the XW-Pro was using all of the excess power to charge the battery bank. As the sun went down, it seamlessly reduced the charge current and then started using battery power to supply the loads. The Enphase software only reported the error of the panels that had shut down. Enphase is working on a software update as they have seen the same thing happen with Tesla Powerwall2 installations. I think it won't be a problem at all if I have more load on the system, or if the sun is down when the power fails. In every case, when the sun comes up, all panels work perfectly. It has only been an issue when the solar was producing more power than my load when the power cut.
I have found an odd problem in the Schneider software that does cause one issue though. I also want to time shift some power from when there is excess solar to the evening 4PM to 9PM peak "Time of Use" rate. So I have it programmed to top up the battery from 9AM to 4PM, and then switch to grid support and help power my home from 4PM to 9PM. But the grid support always stops producing power 0.5 volts above the point where the battery voltage will trigger a recharge. But then it won't charge, because the battery is still above the recharge voltage setting. It is a very stupid error in the program, but Schneider does not seem to care. It does not hurt the backup power mode at all, it is only an issue with the grid being up. Their "Fix" is to use DC coupled solar to provide the charge. That is certainly not practical as a retrofit to a micro inverter system. I hope they will issue a software patch for AC coupled, but so far they have not. My data has been sent to their engineers, or at least they said it was.
My "fix" is a work in progress. I have it narrowed down to only having to change the value of 2 numbers in the settings 2 times a day. I am programming a micro controller to send the commands. I am just working out the timing now. It seems the responses from the XW-Pro inverter are quite slow and my software is not waiting long enough for the replies. I hope to have it all worked out soon. The XW-Pro inverter is a great piece of hardware and has no issues cranking out far more power than I will ever need. My only issue is this power time shifting to save a few bucks on my electric bill to try to offset some of the cost. I have been manually changing the values most days, and I have been able to shave off nearly $2 a day on average with the time shifting. That comes out to nearly $700 a year. So I want to make it work. And if I can get So Cal Edison to move me to the Prime D rate, I will save even more.
newbostonconst
Solar Enthusiast
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Outback, Solark, Schneider plus more have hybrid inverters that will throttle back your Enphase inverters.
I have IQ7's running with an Outback. I would call Alte or another supplier to help with sizing and the like.
www.altestore.com
I have IQ7's running with an Outback. I would call Alte or another supplier to help with sizing and the like.
Hybrid Inverter | Hybrid Solar Inverter | altE
Hybrid inverters, mostly used in grid-tie solar systems, can provide backup power when the electric grid fails. Call 877-878-4060 to size your system today.
www.altestore.com
GXMnow
Solar Wizard
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- Jul 17, 2020
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I bought my Schneider XW-Pro from "Real Goods" which is a California arm of Alt E Store. I caught a 10% off sale and free shipping.
If I was going to do it again.. I may have gone with the Outback Skybox. It costs a bit more, and is a little less power, but everything you need is all in one box. I also had to buy a UL rated conduit box and the gateway just to get the XW-Pro connected. The Skybox even has a DC coupled MPPT controller if you want to add a few DC panels, but it also works just AC coupled. A Schneider MPPT controller is close to $1,000.
As a backup inverter, the Schneider is hard to beat. This thing is very solid. It is built to take it and has a 10 year warranty once you register it. It is pretty efficient and puts out solid clean power. My only regret is the time of use power shifting issue. From what I understand, the Outback Skybox handles that without a problem. The Sol Ark did not recommend running my 4,800 watts of solar panels in an AC coupled only setup. I am not sure if that is a serious limitation, or just an efficiency issue or what.
I have not done any kind of long term test yet, but from the descriptions, all of the majors that are rated for AC coupling will do the frequency shift power curtailment on solar inverters that support it. I have not had mine in a backup off grid mode long enough with decent sun to see it go into that mode yet. Basically, if the solar power coming in exceeds what the loads need, it will use the extra power to charge the batteries. If this power is greater than the maximum charge rate, or if the batteries are getting full, the inverter will shift the line frequency up. Most newer solar inverters should be able to be set in a grid profile that will cause the inverter to curtail it's output as a ratio of the line frequency. Enphase calls it Frequency/Watt control. I have that turned on by using the California "Rule 21" grid profile. As I am in So Cal, I need to be in this mode anyways to be legal.
If I was going to do it again.. I may have gone with the Outback Skybox. It costs a bit more, and is a little less power, but everything you need is all in one box. I also had to buy a UL rated conduit box and the gateway just to get the XW-Pro connected. The Skybox even has a DC coupled MPPT controller if you want to add a few DC panels, but it also works just AC coupled. A Schneider MPPT controller is close to $1,000.
As a backup inverter, the Schneider is hard to beat. This thing is very solid. It is built to take it and has a 10 year warranty once you register it. It is pretty efficient and puts out solid clean power. My only regret is the time of use power shifting issue. From what I understand, the Outback Skybox handles that without a problem. The Sol Ark did not recommend running my 4,800 watts of solar panels in an AC coupled only setup. I am not sure if that is a serious limitation, or just an efficiency issue or what.
I have not done any kind of long term test yet, but from the descriptions, all of the majors that are rated for AC coupling will do the frequency shift power curtailment on solar inverters that support it. I have not had mine in a backup off grid mode long enough with decent sun to see it go into that mode yet. Basically, if the solar power coming in exceeds what the loads need, it will use the extra power to charge the batteries. If this power is greater than the maximum charge rate, or if the batteries are getting full, the inverter will shift the line frequency up. Most newer solar inverters should be able to be set in a grid profile that will cause the inverter to curtail it's output as a ratio of the line frequency. Enphase calls it Frequency/Watt control. I have that turned on by using the California "Rule 21" grid profile. As I am in So Cal, I need to be in this mode anyways to be legal.
Hedges
I See Electromagnetic Fields!
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It looks to me like Rule 21 profile will work nicely above 60.5 Hz up to 62 Hz for 5 minutes, then go offline.
solarbuildermag.com
So when PV production is excessive, the inverter will curtail power to match load for 5 minutes. Then it goes off line and you run on batteries for 5 minutes. Then it comes back on-line and things are fine while battery recharges, followed by repeat of the cycle.
Unless max current battery wants at that time is less than the surplus available, in which case the 5 minute ride-through countdown restarts immediately.
Kinda-sorta better, but not great. I prefer an inverter like I have with off-grid profile, will hang out indefinitely between 61 Hz and 62 Hz, delivering exactly what loads and battery need.
How California’s Rule 21 inverter requirements expand grid capacity, limit energy (revenue) generation
A multi-year effort has been ongoing in California to update technical requirements for connecting Distributed Energy Resources (DER) to the grid, known as Rule 21. The experience of Germany was cited as one reason to take action. In Germany, significant grid destabilization problems arose when...
solarbuildermag.com
So when PV production is excessive, the inverter will curtail power to match load for 5 minutes. Then it goes off line and you run on batteries for 5 minutes. Then it comes back on-line and things are fine while battery recharges, followed by repeat of the cycle.
Unless max current battery wants at that time is less than the surplus available, in which case the 5 minute ride-through countdown restarts immediately.
Kinda-sorta better, but not great. I prefer an inverter like I have with off-grid profile, will hang out indefinitely between 61 Hz and 62 Hz, delivering exactly what loads and battery need.
GXMnow
Solar Wizard
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Hopefully, it will curtail enough at less than 61.5 Hz as there it can stay running and not shut down. It just needs to drop production to match the load to float the batteries. But yes, if solar production is too much, it will go to where it still has to shut off and run on battery a bit. Cycling every 5 minutes is not too terrible. This will only happen once the battery is full. If you just ran on battery all night, it may take all day to recover. In my case, I might use 8 KWH overnight. When the sun comes back up, I will still be drawing that 700-800 watts. So it only charges when the solar exceeds that. Then it has to reach full charge. Looking at my production graphs, it won't top up the 10 KWH taken out of the battery until 3PM and the solar production is already falling off. It may only have to curtail for an hour or two until the solar production is less than the draw in the house. At that time, it has to start using some battery power again. Solar end up hitting zero after 6 PM and I would be on battery alone until 8 am the next morning to restart the cycle. The last 10 days, it has been cool but clear, so even with the shorter days, my 16 panels have been making between 17.8 and 20.3 KWH every day. In summer, I was topping 30 KWH a day, but the A/C was eating way more.
When I am on grid, none of that matters. Any extra solar after my battery is charged and the house load is met just goes out my meter and I get some credit for it. It is at the lower Time of Use rate, but still better than curtailing it and getting no credit. I am allowed to export up to 16 amps peak and 900 KWH a month total. Since adding the battery, I am only exporting 2-4 KWH a day. So less than 10% of what I am allowed. But I am still buying 10 KWH a day on average since my solar array is just not that big. Before the battery, I would export 15 KWH a day, and buy back 25 KWH or so. Once I have my PLC micro controller reliably making changes in the XW inverter, I do plan to have it read my export, and adjust the currents every 5 minutes or so to eliminate all export and use the power myself. Ideally, that could cut my power purchase to under 6 kwh a day. During the summer 100 degree F heat, I still need to buy a fair bit of power, but on moderate cool days, I but zero, and even have a few negative days.
When I am on grid, none of that matters. Any extra solar after my battery is charged and the house load is met just goes out my meter and I get some credit for it. It is at the lower Time of Use rate, but still better than curtailing it and getting no credit. I am allowed to export up to 16 amps peak and 900 KWH a month total. Since adding the battery, I am only exporting 2-4 KWH a day. So less than 10% of what I am allowed. But I am still buying 10 KWH a day on average since my solar array is just not that big. Before the battery, I would export 15 KWH a day, and buy back 25 KWH or so. Once I have my PLC micro controller reliably making changes in the XW inverter, I do plan to have it read my export, and adjust the currents every 5 minutes or so to eliminate all export and use the power myself. Ideally, that could cut my power purchase to under 6 kwh a day. During the summer 100 degree F heat, I still need to buy a fair bit of power, but on moderate cool days, I but zero, and even have a few negative days.
Hedges
I See Electromagnetic Fields!
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Below 60.5 Hz it produces 100%. Above 60.5 Hz it is required to disconnect after 5 minutes. Above 62 Hz, immediately.
Don't know what curve it follows, but mine is 100% up to 61 Hz, linear ramp down to 0% at 62 Hz.
My 10000TLUS didn't implement grid-backup correctly. It stays on up to 64.5 Hz where it disconnected but didn't curtail production below that.
Came back on immediately as frequency was dropping back toward 61 Hz, and repeated.
Workaround for that bug was set to off-grid. It hovers near 62 Hz with no load, lower with moderate load. That seems to work very well, just don't know what it does if a huge 10 kW load turned off all at once (frequency shift is seconds per Hz, and batteries won't accept that many watts.)
What you want are loads that get enabled between 60.5 Hz and 61 Hz, ideally linearly ramping up with frequency.
Don't know what curve it follows, but mine is 100% up to 61 Hz, linear ramp down to 0% at 62 Hz.
My 10000TLUS didn't implement grid-backup correctly. It stays on up to 64.5 Hz where it disconnected but didn't curtail production below that.
Came back on immediately as frequency was dropping back toward 61 Hz, and repeated.
Workaround for that bug was set to off-grid. It hovers near 62 Hz with no load, lower with moderate load. That seems to work very well, just don't know what it does if a huge 10 kW load turned off all at once (frequency shift is seconds per Hz, and batteries won't accept that many watts.)
What you want are loads that get enabled between 60.5 Hz and 61 Hz, ideally linearly ramping up with frequency.
I have another question about your Schneider configuration, which you mentioned above. You said the excess power that isn't used from the power will recharge the battery on the XW. Is it just using that from the output 240v on the device? I'm going to order one in the next week or so and I'm trying to draw up how to connect it with my electrician.
GXMnow
Solar Wizard
- Joined
- Jul 17, 2020
- Messages
- 2,702
I assume you are asking me.
My system is using the Schneider XW-Pro. I am grid tied with backup. I have a breaker in my main panel, which for now is just 20 amps. That is the limit allowed because my main panel is just rated at 100 amps, with a 100 amp main breaker. This is the 120% rule that most areas use.
My Enphase system consists of an iQ Combiner3 box and sixteen 300 watt panels with an iQ7 inverter on each one. The main output of the iQ Combiner is feeding a 20 amp breaker on the "Essential Loads" panel on the output of the XW-Pro inverter. The output of the XW-Pro currently has a 30 amp main breaker in the Essential Loads panel. With a balanced load, that is 7,200 watts, the inverter long term power rating is only 6,800 watts. The loads I want to put in the backup essential loads panel is only going to be about 1,500 - 2,000 watts. My original "Solar System Disconnect" is still at the main output of the EnPhase iQ Combiner. Pulling that switch will cut all power on the roof as required by the fire and electrical codes. I am adding a second switch that will shut down the inverter. I can't find a requirement for this in the code, but I think it makes sense for fire safety to be able to kill all power in a house after an earthquake etc. Inside the garage, I have a battery disconnect switch and there is a Class T fuse inside my battery enclosure to protect all the wiring if anything real bad happens.
My battery bank is on the smaller side at just 360 Amp Hours, but it can take the current since they are very low resistance LG NMC cells. I have it fused at just 200 amps, but the cells can take over 700 amps safely. I may expand the battery a bit more in the future, but this is working well for my current needs. So far, I only have 2 small loads moved over to the essential loads backup panel. I will need to shut down my home and trace out the other circuits because all of the labels got lost when the original Enphase solar was installed. They had to move breakers and didn't trace where they went. Eventually, I will have about 2,000 watts of load in that panel, but for now it is only 500 watts.
While on grid the XW-Pro is basically just going to sit there. It has one software flaw. If left alone, it will charge up the batteries, and can then go into "Grid Support" mode and supply power to both the essential loads panel, and feed back to the main panel, but once the battery is down to 0.5 volt above the "Recharge Volts" setting, it will stop feeding power back out and go into "Stand By" mode. And since the battery is above the recharge volts, it just sits there. I have talked with their engineers about this, and their "fix" is to use DC coupled solar to charge the battery bank. That is not the right solution. In a backup power only system, it will work just fine. You set the Recharge volts up fairly high, and if the battery runs down for any reason, it will charge to full again. When the grid input fails, it will isolate from the grid input and feed the essential loads backup panel. In that mode, it works great. The output is very clean and solid, and the Enphase iQ system does see it as a valid grid so the iQ7 inverters will produce power and feed into the essential loads panel. When it does switch over on the power fail, I have had a few iQ7's lock out, but they always come back in the morning. Enphase is looking into why they locked out. Hopefully a software fix will be coming soon.
While running off grid, the XW-Pro inverter will supply all the power while the sun is down and the batteries will obviously be running down as expected. When the sun comes up and the solar inverters start making power, the solar will now be feeding the loads. If the solar is not enough, the XW-Pro will only drive what is needed to make up the difference. So at 9 am here, if I need 2,000 watts, my solar is making 1,200 watts, the XW-Pro only pulls 800 watts from the batteries. As it get's closer to noon, my solar production reaches 3,500 watts, but the loads only use 2,000 watts, that gives 1,500 watts to charge up the batteries. This is where it get's a bit weird. The XW-Pro will adjust the charge current constantly, to keep the output at 120/240 volts. Just think about a cloud going past. The solar output falls, it has to drop charge current, or even switch back to inverting to keep the panel at 120/240 volts at all times. It does this very quickly and you don't even see it happening. It is virtually seamless and the power output is rock solid. I even tried turning on a 600 watt load and watched it go from 300 watts of charging, to 300 watts of inverting without even a flicker of the LED lights. But for it to work this well, the battery has to be able to accept the power from the solar panels. If you are running at a light load with a lot of solar available, there is a point where two different things can happen. In my case, my battery bank can easily take 100% of my solar output as long as they are not topped out, so the first case won't come up, but if you need to limit charge current due to a battery bank charge rate limit, the XW-Pro will need to limit the output from the solar inverter(s). This is done by using frequency shift. The XW-Pro will raise the line frequency which will cause some inverters to lower their output. If the inverters respond quick enough, it can do a good job of regulating the charge current this way. If they do not respond fast enough, they will end up shutting off as the frequency will shift too far causing a grid fault error in the solar inverter(s). If this happens, the XW-Pro will again switch to inverting and will provide the power to the loads. The frequency will shift back to 60 Hz and after 5 minutes, the solar inverter(s) should resume producing power. This cycle may end up repeating. My iQ7 inverters are set to do the frequency shift power curtailment, but I have not tested it in that mode yet. The only reason my system should go into that mode is if the battery bank reaches full charge. In this case, the XW-Pro will begin to shift the frequency up when the voltage is approaching the Bulk Charge limit. The idea is the same, just for a different reason. Current needs to be limited to keep from overcharging the batteries. With a slow small shift, hopefully, the system will find a balance where the batteries just float and the solar is feeding the loads. The same controls apply here. If a cloud moves across, it will just pull some battery power to make up for it. And the frequency will shift back to 60 Hz again to get as much solar as it can, until the battery is topped up again. My short off grid tests have worked great.
While on grid, I do want to time shift power from when the sun is up to when my grid provider charges the highest On Peak rates in the evening. This is one place where the XW-Pro software is just not working correctly with only having AC coupled solar. To make this work, I have found that I need to adjust two settings twice every day. The "Recharge Volts" and the "Grid Support Volts". I am in the process of programming a small PLC "Programmable Logic Controller" to send those commands to the XW-Pro on a time schedule. I hope to have it working soon. I am just dealing with timing issues now as the XW-Pro is pretty slow to respond to commands. If I manually do each step, it works fine, but when the PLC tries to run through them, it is just too fast and the command is failing. I am trying to write a proper handshake routine where it tests each step for completion. For the past 2 months, I have been manually sending the commands most days (I miss once in a while) and I have been moving about 7 KWH of solar power to the evening with no problem, and it is cutting a chunk off of my electric bill. Using power that costs just $0.22 instead of $0.42 per KWH, so in theory, saving about $1.20 per day. Do that 300 days a year, and it is $360 per year. It won't pay for the batteries, but it sure does help justify the cost of having the backup system.
My system is using the Schneider XW-Pro. I am grid tied with backup. I have a breaker in my main panel, which for now is just 20 amps. That is the limit allowed because my main panel is just rated at 100 amps, with a 100 amp main breaker. This is the 120% rule that most areas use.
My Enphase system consists of an iQ Combiner3 box and sixteen 300 watt panels with an iQ7 inverter on each one. The main output of the iQ Combiner is feeding a 20 amp breaker on the "Essential Loads" panel on the output of the XW-Pro inverter. The output of the XW-Pro currently has a 30 amp main breaker in the Essential Loads panel. With a balanced load, that is 7,200 watts, the inverter long term power rating is only 6,800 watts. The loads I want to put in the backup essential loads panel is only going to be about 1,500 - 2,000 watts. My original "Solar System Disconnect" is still at the main output of the EnPhase iQ Combiner. Pulling that switch will cut all power on the roof as required by the fire and electrical codes. I am adding a second switch that will shut down the inverter. I can't find a requirement for this in the code, but I think it makes sense for fire safety to be able to kill all power in a house after an earthquake etc. Inside the garage, I have a battery disconnect switch and there is a Class T fuse inside my battery enclosure to protect all the wiring if anything real bad happens.
My battery bank is on the smaller side at just 360 Amp Hours, but it can take the current since they are very low resistance LG NMC cells. I have it fused at just 200 amps, but the cells can take over 700 amps safely. I may expand the battery a bit more in the future, but this is working well for my current needs. So far, I only have 2 small loads moved over to the essential loads backup panel. I will need to shut down my home and trace out the other circuits because all of the labels got lost when the original Enphase solar was installed. They had to move breakers and didn't trace where they went. Eventually, I will have about 2,000 watts of load in that panel, but for now it is only 500 watts.
While on grid the XW-Pro is basically just going to sit there. It has one software flaw. If left alone, it will charge up the batteries, and can then go into "Grid Support" mode and supply power to both the essential loads panel, and feed back to the main panel, but once the battery is down to 0.5 volt above the "Recharge Volts" setting, it will stop feeding power back out and go into "Stand By" mode. And since the battery is above the recharge volts, it just sits there. I have talked with their engineers about this, and their "fix" is to use DC coupled solar to charge the battery bank. That is not the right solution. In a backup power only system, it will work just fine. You set the Recharge volts up fairly high, and if the battery runs down for any reason, it will charge to full again. When the grid input fails, it will isolate from the grid input and feed the essential loads backup panel. In that mode, it works great. The output is very clean and solid, and the Enphase iQ system does see it as a valid grid so the iQ7 inverters will produce power and feed into the essential loads panel. When it does switch over on the power fail, I have had a few iQ7's lock out, but they always come back in the morning. Enphase is looking into why they locked out. Hopefully a software fix will be coming soon.
While running off grid, the XW-Pro inverter will supply all the power while the sun is down and the batteries will obviously be running down as expected. When the sun comes up and the solar inverters start making power, the solar will now be feeding the loads. If the solar is not enough, the XW-Pro will only drive what is needed to make up the difference. So at 9 am here, if I need 2,000 watts, my solar is making 1,200 watts, the XW-Pro only pulls 800 watts from the batteries. As it get's closer to noon, my solar production reaches 3,500 watts, but the loads only use 2,000 watts, that gives 1,500 watts to charge up the batteries. This is where it get's a bit weird. The XW-Pro will adjust the charge current constantly, to keep the output at 120/240 volts. Just think about a cloud going past. The solar output falls, it has to drop charge current, or even switch back to inverting to keep the panel at 120/240 volts at all times. It does this very quickly and you don't even see it happening. It is virtually seamless and the power output is rock solid. I even tried turning on a 600 watt load and watched it go from 300 watts of charging, to 300 watts of inverting without even a flicker of the LED lights. But for it to work this well, the battery has to be able to accept the power from the solar panels. If you are running at a light load with a lot of solar available, there is a point where two different things can happen. In my case, my battery bank can easily take 100% of my solar output as long as they are not topped out, so the first case won't come up, but if you need to limit charge current due to a battery bank charge rate limit, the XW-Pro will need to limit the output from the solar inverter(s). This is done by using frequency shift. The XW-Pro will raise the line frequency which will cause some inverters to lower their output. If the inverters respond quick enough, it can do a good job of regulating the charge current this way. If they do not respond fast enough, they will end up shutting off as the frequency will shift too far causing a grid fault error in the solar inverter(s). If this happens, the XW-Pro will again switch to inverting and will provide the power to the loads. The frequency will shift back to 60 Hz and after 5 minutes, the solar inverter(s) should resume producing power. This cycle may end up repeating. My iQ7 inverters are set to do the frequency shift power curtailment, but I have not tested it in that mode yet. The only reason my system should go into that mode is if the battery bank reaches full charge. In this case, the XW-Pro will begin to shift the frequency up when the voltage is approaching the Bulk Charge limit. The idea is the same, just for a different reason. Current needs to be limited to keep from overcharging the batteries. With a slow small shift, hopefully, the system will find a balance where the batteries just float and the solar is feeding the loads. The same controls apply here. If a cloud moves across, it will just pull some battery power to make up for it. And the frequency will shift back to 60 Hz again to get as much solar as it can, until the battery is topped up again. My short off grid tests have worked great.
While on grid, I do want to time shift power from when the sun is up to when my grid provider charges the highest On Peak rates in the evening. This is one place where the XW-Pro software is just not working correctly with only having AC coupled solar. To make this work, I have found that I need to adjust two settings twice every day. The "Recharge Volts" and the "Grid Support Volts". I am in the process of programming a small PLC "Programmable Logic Controller" to send those commands to the XW-Pro on a time schedule. I hope to have it working soon. I am just dealing with timing issues now as the XW-Pro is pretty slow to respond to commands. If I manually do each step, it works fine, but when the PLC tries to run through them, it is just too fast and the command is failing. I am trying to write a proper handshake routine where it tests each step for completion. For the past 2 months, I have been manually sending the commands most days (I miss once in a while) and I have been moving about 7 KWH of solar power to the evening with no problem, and it is cutting a chunk off of my electric bill. Using power that costs just $0.22 instead of $0.42 per KWH, so in theory, saving about $1.20 per day. Do that 300 days a year, and it is $360 per year. It won't pay for the batteries, but it sure does help justify the cost of having the backup system.
GXMnow
Solar Wizard
- Joined
- Jul 17, 2020
- Messages
- 2,702
I did reply in your PM with a detailed message, but I will repeat most of it here in case others are also having an issue.
On 2 year old firmware, my iQ7's would all shut down when the system went into off grid mode. I think it was just the glitch of switching from failing grid to battery, but the bad part is they would lock out and not come back online, until the sun went down and came back up, or if you cover the solar panel and uncover it again.
The first time this happened, and I was off grid for 3 hours and my battery bank was fading, Enphase was able to remote in and change the grid profile. This basically had the effect of resetting the panels, and all 16 came back on and my system was charging again, but the sun was also going down. I got less than an hour of charging before I was back running on batteries for the evening. The grid came back up at about 1 am and the system worked fine when the sun came up.
On this new power failure, almost 2 days ago, only 5 panels shut down at first, and then 4 more. So I was down to just 5 panels in the early morning. I could see them cycle on and off, like they were testing the grid, and it was not stable enough. They were still in a generic IEEE grid profile, which is pretty picky. I was able to log in with Enphase installer toolkit, and I told the Envoy to change the grid profile back to "CA Rule 21". Rule 21 allows for more grid fluctuation, and has ride through and frequency/watt curtailment which helps in an AC coupled setup. Enphase had updated my firmware twice since the last outage, and said they should work better off grid now. Once I was on Rule 21, all 16 of my panels started producing power and I was powering my backup loads, and charging at over 1,000 watts into my battery bank.
The power was only off for 90 minutes, but in that time, the sun cam up enough, that my system hit my current max charge rate setting, so it did frequency shift to slow the charging. I was not home to watch it, so I only have the logs to see what it did. 5 of my panels were cycling off and back on to keep the charge current under my 18% setting, about 23.4 amps. If I was home, I would have set it higher. It was odd that it was always the same 5 panels that were cycling off, but they only cut out for 1 minute, not 5. So the power loss was not much, and it was doing this to keep the charge current safe based on my settings.
If your Enphase iQ7's stop outputting, the best solution I have found is changing the grid profile. If you can get to them, also try covering the panel to shut off the DC power, and then uncover them, that resets them and they come back online. While running AC coupled off of an inverter, they also seem to work much better using a CA Rule 21 grid profile. Even if you are not in California, the grid profile rules make them more tolerant of power fluctuations.
On 2 year old firmware, my iQ7's would all shut down when the system went into off grid mode. I think it was just the glitch of switching from failing grid to battery, but the bad part is they would lock out and not come back online, until the sun went down and came back up, or if you cover the solar panel and uncover it again.
The first time this happened, and I was off grid for 3 hours and my battery bank was fading, Enphase was able to remote in and change the grid profile. This basically had the effect of resetting the panels, and all 16 came back on and my system was charging again, but the sun was also going down. I got less than an hour of charging before I was back running on batteries for the evening. The grid came back up at about 1 am and the system worked fine when the sun came up.
On this new power failure, almost 2 days ago, only 5 panels shut down at first, and then 4 more. So I was down to just 5 panels in the early morning. I could see them cycle on and off, like they were testing the grid, and it was not stable enough. They were still in a generic IEEE grid profile, which is pretty picky. I was able to log in with Enphase installer toolkit, and I told the Envoy to change the grid profile back to "CA Rule 21". Rule 21 allows for more grid fluctuation, and has ride through and frequency/watt curtailment which helps in an AC coupled setup. Enphase had updated my firmware twice since the last outage, and said they should work better off grid now. Once I was on Rule 21, all 16 of my panels started producing power and I was powering my backup loads, and charging at over 1,000 watts into my battery bank.
The power was only off for 90 minutes, but in that time, the sun cam up enough, that my system hit my current max charge rate setting, so it did frequency shift to slow the charging. I was not home to watch it, so I only have the logs to see what it did. 5 of my panels were cycling off and back on to keep the charge current under my 18% setting, about 23.4 amps. If I was home, I would have set it higher. It was odd that it was always the same 5 panels that were cycling off, but they only cut out for 1 minute, not 5. So the power loss was not much, and it was doing this to keep the charge current safe based on my settings.
If your Enphase iQ7's stop outputting, the best solution I have found is changing the grid profile. If you can get to them, also try covering the panel to shut off the DC power, and then uncover them, that resets them and they come back online. While running AC coupled off of an inverter, they also seem to work much better using a CA Rule 21 grid profile. Even if you are not in California, the grid profile rules make them more tolerant of power fluctuations.
I setup the CA grid code and didn't have any better luck. It started to charge and run my loads and then the XW went to 62 hertz and shut down all of the IQ7. I was about a half volt below my charging set point. I turned off the power to the panels to try and reset them and it did nothing. Was I too close to my max charging voltage? Have you got yours to work with all of your Enphase micro inverters? Enphase and Schneider both tell me that it will not work. Can you tell me where I can down load the latest firm ware for the XWPro 6848?
newbostonconst
Solar Enthusiast
- Joined
- Sep 24, 2019
- Messages
- 1,004
Maybe you can't under normal charging force enough power into your batteries ( meaning your batteries aren't big enough ) or you don't have your charge rate set high enough to absorb the power coming from the panel.
What size battery do you have and how much solar?
Do you have a shunt to be able to tell the state of charge of the batteries. If the batteries are full it will make the panels cycle on and off.
What size battery do you have and how much solar?
Do you have a shunt to be able to tell the state of charge of the batteries. If the batteries are full it will make the panels cycle on and off.
GXMnow
Solar Wizard
- Joined
- Jul 17, 2020
- Messages
- 2,702
Oats49250,
Are you running fully off grid, or are you grid tied and it went off grid from a failure?
Check your Enphase firmware version, see if it is up to date. My iQ7's all locked out when it went from grid to inverter before the latest update. The only ways I was able to reset them and get them back online was to either interrupt the DC power, which I did by covering the panel to lock the sun, sending a grid code change command from the Enphase installer toolkit, or having Enphase support change the grid code remotely, if they are still on the internet. Disconnecting the AC side and connecting them again did not reset them on the old firmware.
On the newer Enphase firmware, they seem to act much better. A few did go offline when the grid failed and the XW took over forming the grid, but about half of them came back online without an issue. I had to leave for work, so I was not patient enough to see if they would all come back on their own, so I sent the command to change them to another CA Rule 21 grid code, and they all came up and started charging my battery through the XW-Pro again.
Looking at my Enphase Enlighten data, and the battery summary from the XW-Pro, it stayed charging just fine, on all 16 iQ7 inverters until the sun was high enough to hit my set max charge current. I forgot to change it for off grid mode so it was still set to just 17%, or about 23 amps. So at that point, I can see where the XW-Pro started doing the frequency shifting. It shifted enough that 5 of my panels went offline, but they came back on in under 5 minutes with no human intervention.
The grid code I am currently on is (CA Rule 21 201902 VV VW FW)
My firmware was update in March 2021 to 520-00082-r01-v04.27.04
Here is a screen shot from the Enphase App.
There are a couple other CA Rule 21 options, but this one actually has FW in the name, which I am pretty sure means "Frequency Watt" output limiting capability. I do not have many outages here, so I may have to simulate one by cutting off the breaker. If I do have the iQ7's lock out again, I do know that changing the grid code wakes them back up.
I do think the Schneider is a bit optimistic about the XW-Pro being able to cut over to backup mode in just 8 milliseconds. It is fast, and my PC's as well as a lot of other gear certainly did not glitch at all on the switchover, but the interruption was enough to cause the iQ7's to see a bad grid condition. I was actually working on my PC when the last grid failure occurred, and I could hear my refrigerator compressor running in the kitchen, and some lights were on. I honestly didn't even notice that the power had failed. One of my background windows had the status page for the XW-Pro inverter, and I saw the dots were moving out of the battery instead of into it. Went I looked to see why, I saw the grid volts were at zero. It was still early in the morning, so the solar was not making enough to keep up, but on top of that, 9 of my 16 panels were in a grid instability error condition.
My XW-Pro is still running on the older 1.08 firmware. I do plan to update it soon, but I most likely will need to shut down my system and that takes out the network that I need to do the update. I used to have a stand alone UPS just for that, but the battery in the UPS died, and I just have not gotten around to fixing that. The XW-Pro is a far better UPS.
Are you running fully off grid, or are you grid tied and it went off grid from a failure?
Check your Enphase firmware version, see if it is up to date. My iQ7's all locked out when it went from grid to inverter before the latest update. The only ways I was able to reset them and get them back online was to either interrupt the DC power, which I did by covering the panel to lock the sun, sending a grid code change command from the Enphase installer toolkit, or having Enphase support change the grid code remotely, if they are still on the internet. Disconnecting the AC side and connecting them again did not reset them on the old firmware.
On the newer Enphase firmware, they seem to act much better. A few did go offline when the grid failed and the XW took over forming the grid, but about half of them came back online without an issue. I had to leave for work, so I was not patient enough to see if they would all come back on their own, so I sent the command to change them to another CA Rule 21 grid code, and they all came up and started charging my battery through the XW-Pro again.
Looking at my Enphase Enlighten data, and the battery summary from the XW-Pro, it stayed charging just fine, on all 16 iQ7 inverters until the sun was high enough to hit my set max charge current. I forgot to change it for off grid mode so it was still set to just 17%, or about 23 amps. So at that point, I can see where the XW-Pro started doing the frequency shifting. It shifted enough that 5 of my panels went offline, but they came back on in under 5 minutes with no human intervention.
The grid code I am currently on is (CA Rule 21 201902 VV VW FW)
My firmware was update in March 2021 to 520-00082-r01-v04.27.04
Here is a screen shot from the Enphase App.
There are a couple other CA Rule 21 options, but this one actually has FW in the name, which I am pretty sure means "Frequency Watt" output limiting capability. I do not have many outages here, so I may have to simulate one by cutting off the breaker. If I do have the iQ7's lock out again, I do know that changing the grid code wakes them back up.
I do think the Schneider is a bit optimistic about the XW-Pro being able to cut over to backup mode in just 8 milliseconds. It is fast, and my PC's as well as a lot of other gear certainly did not glitch at all on the switchover, but the interruption was enough to cause the iQ7's to see a bad grid condition. I was actually working on my PC when the last grid failure occurred, and I could hear my refrigerator compressor running in the kitchen, and some lights were on. I honestly didn't even notice that the power had failed. One of my background windows had the status page for the XW-Pro inverter, and I saw the dots were moving out of the battery instead of into it. Went I looked to see why, I saw the grid volts were at zero. It was still early in the morning, so the solar was not making enough to keep up, but on top of that, 9 of my 16 panels were in a grid instability error condition.
My XW-Pro is still running on the older 1.08 firmware. I do plan to update it soon, but I most likely will need to shut down my system and that takes out the network that I need to do the update. I used to have a stand alone UPS just for that, but the battery in the UPS died, and I just have not gotten around to fixing that. The XW-Pro is a far better UPS.
I do have a shunt and I discharged the batteries to check and they started to charge then they quit, only got up to 5 amps. My battery bank is a used nissan leaf and it is about 40k of usable power. I have the same grid profile CA Rule 21, but mine ends in (1.2.8). My current soft ware is 05.00.55, I cant find a firmware. My Schneider is Build Number 1.11.00bn28. I have tried everything, I believe my problem is the xwpro starts shifting the frequency up as the Enphase come on line. This starts shutting them down, any help would be great. Links to firm ware or grid profiles,
I have had no luck running off grid. My enphase are in strings of 16, I have tried running 16, 32, with the same results. I did run off grid last night with little power coming in and it seemed to work fine adding the power to my loads.
I found my firmware on my Enphase, it is the same as what you have.
I have had no luck running off grid. My enphase are in strings of 16, I have tried running 16, 32, with the same results. I did run off grid last night with little power coming in and it seemed to work fine adding the power to my loads.
I found my firmware on my Enphase, it is the same as what you have.
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I turned on soc in the charge section, and I was able to charge at 5 amps. Still low for 32 Iq7 and 4000 watts of power, when my loads were only 500 watts. Since I have switched to the CA profile the inverters seem more responsive, now I need to figure out why the XW keeps shifting the frequency. It starts of at 60hz and then goes up as the IQ7 come online. After turning on the SOC setting it only went up a little, I think it went up to 60.1hz. Any ideas on what is causing this?
GXMnow
Solar Wizard
- Joined
- Jul 17, 2020
- Messages
- 2,702
When you tried to run off grid, what other loads were on the system?
In my case, I had my refrigerator, 3 PC's, some LED lights, and a few other small devices. All together, the draw was about 800 watts, with a mix of power supplies and inductive loads. Very little was resistive load. The power factor reported by the iQ7's was down to about 0.8 which is not great, but it makes sense with mostly inductive loads. My battery bank was down to about 55% state of charge, and my cells are very stiff, with very low series resistance. I don't know how much difference that might make, but these LG cells are unusually low resistance. If you had a very light load on the system, it might be more difficult for it to remain stable. If all of the power from the iQ7's has to be pulled in to charge the batteries, that might be a problem. Try adding a bit more load current and see what it does.
Can you post a screen shot of the "Battery Summary" graph for when it was trying to run off grid? What is your absorb voltage set to? What is the max charge current set at?
The XW-Pro should only frequency shift to either limit the charge current, or stop the charge because the battery bank is full. We should be able to see if that was happening in the battery summary graph. It does not take much resistance from a marginal connection to cause the voltage to rise when it tries to charge at 50 amps. The could cause a voltage rise which may trigger a frequency shift as it looks like the battery is getting full.
Also check your line voltage while on grid, and the output voltage of the XW-Pro while off grid. How do you have the output of the inverters connected? Are you using a Schneider panel, or a commercial sub panel? I am using a Square D breaker panel, but I do not have an inverter bypass switch in my system. The output of the XW-Pro goes straight to the main breaker in the small Square D panel, and my Enphase Envoy Combiner is connected to a 20 amp breaker in that same panel. I them have 4 more breakers feeding the essential loads in my home.
In my case, I had my refrigerator, 3 PC's, some LED lights, and a few other small devices. All together, the draw was about 800 watts, with a mix of power supplies and inductive loads. Very little was resistive load. The power factor reported by the iQ7's was down to about 0.8 which is not great, but it makes sense with mostly inductive loads. My battery bank was down to about 55% state of charge, and my cells are very stiff, with very low series resistance. I don't know how much difference that might make, but these LG cells are unusually low resistance. If you had a very light load on the system, it might be more difficult for it to remain stable. If all of the power from the iQ7's has to be pulled in to charge the batteries, that might be a problem. Try adding a bit more load current and see what it does.
Can you post a screen shot of the "Battery Summary" graph for when it was trying to run off grid? What is your absorb voltage set to? What is the max charge current set at?
The XW-Pro should only frequency shift to either limit the charge current, or stop the charge because the battery bank is full. We should be able to see if that was happening in the battery summary graph. It does not take much resistance from a marginal connection to cause the voltage to rise when it tries to charge at 50 amps. The could cause a voltage rise which may trigger a frequency shift as it looks like the battery is getting full.
Also check your line voltage while on grid, and the output voltage of the XW-Pro while off grid. How do you have the output of the inverters connected? Are you using a Schneider panel, or a commercial sub panel? I am using a Square D breaker panel, but I do not have an inverter bypass switch in my system. The output of the XW-Pro goes straight to the main breaker in the small Square D panel, and my Enphase Envoy Combiner is connected to a 20 amp breaker in that same panel. I them have 4 more breakers feeding the essential loads in my home.
I did try it twice that day where I was off grid. After it not working I went back on grid and charged it. Both times small loads 600watts.
I have a Enphase combiner box with 4 - 20 amp strings of 16. That goes into another combiner box for my barn, solar and house. It then back feeds the barn and the house. Once it gets to the house any excess goes out to the grid.
I have a Enphase combiner box with 4 - 20 amp strings of 16. That goes into another combiner box for my barn, solar and house. It then back feeds the barn and the house. Once it gets to the house any excess goes out to the grid.
