CaySol
Solar apprentice
On the iOS app, click on your profile and then normal setting. Then unselect “use new settings page”. Then go to the settings tab on the Flexboss. Scroll down and you should see it.
Flexboss21 and Gridboss
- Thread starter jwy224
- Start date
Usernameinuse
New Member
Wow, I just made a huge realization. The web app and the mobile app are not the same. They feel the same, and have 80% of the same options, but the web is missing things.
Web:
App:
Web is missing everything after Discharge - Peak Shaving.
Setting it to 1 for start and 255 to end seemed to work. Its night, but the smart load breaker has power now during a grid outage.
I will confirm tomorrow that it actually accepts power.
Web:
App:
Web is missing everything after Discharge - Peak Shaving.
Setting it to 1 for start and 255 to end seemed to work. Its night, but the smart load breaker has power now during a grid outage.
I will confirm tomorrow that it actually accepts power.
jwy224
New Member
That’s great news! I hope everything works as expected. I can definitely see the advantage of AC coupling for battery charging, though standard AC coupling from installers already facilitates this—converting solar energy to AC and then using it to charge the inverter. In my view, the real benefit of integrating AC coupling within the EG4 ecosystem is ensuring that the AC solar system remains operational even during a grid outage.
Usernameinuse
New Member
Success!
Turned off grid, and eventually AC coupled grid-tied inverters starting giving power. Took maybe 10 minutes to reflect it.
I just don't know if this was because of firmware, setting change, or both.
Turned off grid, and eventually AC coupled grid-tied inverters starting giving power. Took maybe 10 minutes to reflect it.
I just don't know if this was because of firmware, setting change, or both.
Usernameinuse
New Member
Can anyone recommend a good funnel? I need to put my champagne back in the bottle. I let it run for an hour, and as it got closer to 100% battery, everything went dark. Gridboss/Flexboss/loads. All dead as can be.
Had to flip the grid back on to get anything to light up.
I will be calling support about it, nothing in event log.
Had to flip the grid back on to get anything to light up.
I will be calling support about it, nothing in event log.
AC-CoupleThis
New Member
Any luck with support and finding a resolution? I was super excited reading your previous post, but quickly fell back to earth with your last one. Lol
I’m currently waiting to get the GridBoss installed (and connect my enphase ac coupled system) by the electrician. One that is done, will hook up the Flexboss and batteries.
Last edited:
jwy224
New Member
Maybe set the AC coupled end SOC% to like 95%?
Usernameinuse
New Member
Support couldn't find a culprit, I spent most of the time asking them about why the settings pages don't match up between phone and web. They said they copy/pasted Flexboss21 settings from 18Kpv, and some things copied over that shouldn't have(or something to that effect).
In playing around though, I might have stumble upon the root cause. My guess for now is it has nothing to do with Flex/Gridboss, but is a battery issue.
So 2 nights ago, I wanted to not have my batteries at 100% in prep to test turning off the grid. so I turned on force discharge in the web app, let them discharge about 10 percent or so. Later on my phone, I turned off force discharge, thinking the working mode would go back to backup mode, but it didn't. It went down to self consumption mode. As a matter of fact, you can't turn on backup mode in the app, best I can tell its only in the web app.
Anyway, I wake up in the morning, and batteries are at zero. Well, my fault right, I should have checked. But when I dug into the charts, it was worse. They dropped from 35% to zero in 20 minutes with no change in consumption.
Then, today, again later I tried to enter force discharge mode, and was only getting something 100w even though I had it set to 5KW. I let it sit there for a while and it never budged.
I waited about 5 hours, and now its discharging just fine at 5KW.
So my guess right now is the batteries freaked out for some reason, and since I was disconnected from the grid, everything went black. No breakers tripped, but my garage camera had a very audible click like a relay closing.
For the record, here was close to the time the blackout happened:
Sadly, AC coupling can't be listed as Solar PV, it is just invisible on this graph(even when grid is up). I don't know why it doesn't understand consumption in this mode either. You can see I had excess AC coupled PV power though, since it was charging batteries at 3393w.
Did the batteries suddenly not want any more current and shutdown or something? Again no breaker trips/alarms/events in event log/nothing.
Re-enabling grid required no on/off of any buttons or breakers.
Batteries are 2 wall mount outdoor in parallel. Chargeverter on busbar as well, but was switched off for all this.
Admittedly, batteries are new to me, this could be operator error.
This weekend I am going to try and force it to happen again with the same scenario to see if I can replicate it, so I will keep you posted.
Honestly, after today, I think it will work long term, we are just working out the hiccups.
I don't mind being the beta tester. My wife on the other hand.....
In playing around though, I might have stumble upon the root cause. My guess for now is it has nothing to do with Flex/Gridboss, but is a battery issue.
So 2 nights ago, I wanted to not have my batteries at 100% in prep to test turning off the grid. so I turned on force discharge in the web app, let them discharge about 10 percent or so. Later on my phone, I turned off force discharge, thinking the working mode would go back to backup mode, but it didn't. It went down to self consumption mode. As a matter of fact, you can't turn on backup mode in the app, best I can tell its only in the web app.
Anyway, I wake up in the morning, and batteries are at zero. Well, my fault right, I should have checked. But when I dug into the charts, it was worse. They dropped from 35% to zero in 20 minutes with no change in consumption.
Then, today, again later I tried to enter force discharge mode, and was only getting something 100w even though I had it set to 5KW. I let it sit there for a while and it never budged.
I waited about 5 hours, and now its discharging just fine at 5KW.
So my guess right now is the batteries freaked out for some reason, and since I was disconnected from the grid, everything went black. No breakers tripped, but my garage camera had a very audible click like a relay closing.
For the record, here was close to the time the blackout happened:
Sadly, AC coupling can't be listed as Solar PV, it is just invisible on this graph(even when grid is up). I don't know why it doesn't understand consumption in this mode either. You can see I had excess AC coupled PV power though, since it was charging batteries at 3393w.
Did the batteries suddenly not want any more current and shutdown or something? Again no breaker trips/alarms/events in event log/nothing.
Re-enabling grid required no on/off of any buttons or breakers.
Batteries are 2 wall mount outdoor in parallel. Chargeverter on busbar as well, but was switched off for all this.
Admittedly, batteries are new to me, this could be operator error.
This weekend I am going to try and force it to happen again with the same scenario to see if I can replicate it, so I will keep you posted.
Honestly, after today, I think it will work long term, we are just working out the hiccups.
I don't mind being the beta tester. My wife on the other hand.....
Usernameinuse
New Member
Good idea, I will test it this weekend.
coach222
New Member
The "helper" (? mark) next to AC Couple SOC End (%) says:
"In off grid mode, it exits AC couple after SOC reaches End SOC.Set to 101%, allowing the AC Couple bypass to take load after being fully charged"
I haven't disconnected the grid to test it but I set it at 101%...
"In off grid mode, it exits AC couple after SOC reaches End SOC.Set to 101%, allowing the AC Couple bypass to take load after being fully charged"
I haven't disconnected the grid to test it but I set it at 101%...
Usernameinuse
New Member
Thats where the UI is just so hard to understand. I interpreted that as when you have this setting enabled:
Not when it is disabled, but the grid just happens to be down state.
Not when it is disabled, but the grid just happens to be down state.
skimandan
New guy
It seems the reason there is not a quality operation manual for the FlexBoss21 and less so the GridBoss is that the settings pages are such utter garbage. Can you imagine trying to write this in a technical manual?
I'm glad they are continuing to work on the settings but I fear the documentation will continue to diverge from reality.
Usernameinuse
New Member
Ok, progress! Here is how you can get is working.
Step one: Take your kids to a birthday party and let your wife stay home so you earn enough credits for the later power outages.
I put a multimeter on the smartport AC couple breaker, then put a camera on it so I could use web interface and phone app, and take screenshots.
Here are the results.
The discharge settings in the mobile app are irrelevant. They don't do anything.
When disconnected from the grid, the AC couple settings don't make sense, but here is how they work.
Battery state of 84%.
start at 1, end at 90. No voltage on the breaker.
Battery state of 84%
start at 85, end at 90, and there IS voltage on that breaker, which wakes up the inverters and starts producing power.
It makes less sense as we go along though. I set the start to 87 while the battery was 86, but it blew right past it and continued
Now we at least know how the setting "works" in on grid mode, when the grid is down.
at 89% SOC, and about 50 minutes after I flipped off the grid, total blackout again. I had upped the end SOC to 92 at this point.
I added another multimeter to measure battery voltage, but forgot the camera was wireless attached to a AP not on UPS, so it died.
These were values an instant before blackout:
Battery charging hit its peak right around then, but could be a coincidence:
Step one: Take your kids to a birthday party and let your wife stay home so you earn enough credits for the later power outages.
I put a multimeter on the smartport AC couple breaker, then put a camera on it so I could use web interface and phone app, and take screenshots.
Here are the results.
The discharge settings in the mobile app are irrelevant. They don't do anything.
When disconnected from the grid, the AC couple settings don't make sense, but here is how they work.
Battery state of 84%.
start at 1, end at 90. No voltage on the breaker.
Battery state of 84%
start at 85, end at 90, and there IS voltage on that breaker, which wakes up the inverters and starts producing power.
It makes less sense as we go along though. I set the start to 87 while the battery was 86, but it blew right past it and continued
Now we at least know how the setting "works" in on grid mode, when the grid is down.
at 89% SOC, and about 50 minutes after I flipped off the grid, total blackout again. I had upped the end SOC to 92 at this point.
I added another multimeter to measure battery voltage, but forgot the camera was wireless attached to a AP not on UPS, so it died.
These were values an instant before blackout:
Battery charging hit its peak right around then, but could be a coincidence:
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AC-CoupleThis
New Member
I’m new to the game here so please forgive me for the dumb questions.
Just want to make sure I understand the logic in layman’s terms:
1. The only way to activate the ac coupled SP is to make sure the battery start SOC is essentially 99%, (otherwise it will not know when to wake up?)
2. I see your consumption was 0W. I know you said there was a load but you were not measuring it, however, do you think there is a load threshold that is needed to activate the SP?
Usernameinuse
New Member
Let me take a step back:
When the grid is up, everything works very well. The SOC start/stop work exactly as you would think. I set mine to 1 - 101, and AC coupled solar works well, feeds back to grid when batteries full. The only downside is that in the graph, it doesn't categorize it as solar, so the graphs are wrong, and consumption goes down to zero, and grid goes into the positive when I have excess PV and it is selling back to the grid.
When I turn the grid off with a breaker, all hell breaks lose.
Flexboss21 takes over and does supply loads.
It never says the grid goes down, just says this:
Mobile app does not trigger grid outage notification.
AC coupling settings suddenly go into that bizarre config I showed above. Feels like a bug, I doubt they would program it that way.
AC coupling eventually causes some kind of issue that causes blackout. Has happened twice to me now. I tested again today with disabling ac coupling and ran 2 hours with no issue off grid.
To answer your questions.
1.Its different between grid up and down. Up operates as normal (1-101), down, you are correct, start at 99 works, but feel like this must be a bug.
2. Unknown. I always have some kind of load so hard to test.
When the grid is up, everything works very well. The SOC start/stop work exactly as you would think. I set mine to 1 - 101, and AC coupled solar works well, feeds back to grid when batteries full. The only downside is that in the graph, it doesn't categorize it as solar, so the graphs are wrong, and consumption goes down to zero, and grid goes into the positive when I have excess PV and it is selling back to the grid.
When I turn the grid off with a breaker, all hell breaks lose.
Flexboss21 takes over and does supply loads.
It never says the grid goes down, just says this:
Mobile app does not trigger grid outage notification.
AC coupling settings suddenly go into that bizarre config I showed above. Feels like a bug, I doubt they would program it that way.
AC coupling eventually causes some kind of issue that causes blackout. Has happened twice to me now. I tested again today with disabling ac coupling and ran 2 hours with no issue off grid.
To answer your questions.
1.Its different between grid up and down. Up operates as normal (1-101), down, you are correct, start at 99 works, but feel like this must be a bug.
2. Unknown. I always have some kind of load so hard to test.
Please help me t understand the FlexBoss MPPT and how it applies to string design.
What happens when the voltage rises above the "full power MPPT Voltage range"? Will it deliver less than 9360W per large MPPT?
The "Max. utilized solar power" is 21kW, while the max output is 16kW. Do I understand it correctly that the remaining 5kW can be used only to charge the battery? Can it be configured to charge only when the excess power is available?
What do you think of this string design? It slightly oversubscribes the inverter.
What happens when the voltage rises above the "full power MPPT Voltage range"? Will it deliver less than 9360W per large MPPT?
The "Max. utilized solar power" is 21kW, while the max output is 16kW. Do I understand it correctly that the remaining 5kW can be used only to charge the battery? Can it be configured to charge only when the excess power is available?
What do you think of this string design? It slightly oversubscribes the inverter.
skimandan
New guy
I’ll take a stab at this.
The specs and manual use lots of wiggle words that are used in a way to roughly describe the behavior of the flexboss21. If you look at my posts you’ll see my trail of complaints about this.
What does full power mean? Who knows, but I’ll guess it is most efficient use of the dc. The software does not report dc to ac conversion efficiency so you’ll likely never know.
Bottom line is that your string will work fine but might clip a few hundred watts a few times a month when your Amps exceed the max mppt spec when it’s cold and sunny. Since your Voltage is under max you won’t hurt the inverter.
You might be able to get the battery charge to match times you have more than 16kW PV using self consumption or working modes.
Thanks, @skimandan I agree, the wording is as clear as mud. What do they mean by "Full power at 250-440V"? Since MPPT has a 26A max. current, it can't reach its full 9600W until the voltage hits 360V.
I have a luxpower 6kw.
per spec max pv input is 9kw, (although i am able to see it utilize ~10kw)
assuming-
solar panels can provide 9kw
2 kw load
charging will be clipped at 6kw.
remaining 1kw is wasted.
The mppt compensates by increasing string voltage.
it works that way by default
Forgot to say the other way around
assuming-
solar panels can provide 9kw
7kw load (yep. my 6kw luxpower can give EPS output more than it's rated for a few minutes, unsure how long)
excess 2kw will go to charge the batteries
Every brand/model may react differently.
above is data for 18k PV.
ymmv for others. idk.
wheisenburg
Owner Operator of Heisenberg Electric
So, first of all, AC Coupling and DC Coupling refer to how does power flow from your PV panels to your batteries.
When your system is connected to the grid and you are using grid tied inverters, you are simply operating the system in pass through mode. Your grid tied inverters are directly connected to the grid. This is not really AC coupling because your Hybrid inverters are not interacting with your grid tied inverters. If you have DC Coupled solar, that will work whether or not you are off grid. The DC flows to the DC bus. There it can either charge the batteries or be converted to AC and consumed or exported.
AC Coupled means that power can flow from your grid tied inverters to your loads. Your hybrid inverters will also be connected to your loads. Depending on your loads and your PV production, your hybrid inverters will either make up the needed power for the loads or store the excess power in the batteries.
In addition an AC Coupled system needs to insure that the batteries don't become over charged. Some systems do this by just cycling the grid tied inverters on and off. Others by using the frequency curtailment built into the grid tied inverters.
So to say that AC Coupling only works "when the grid is present" is to say AC Couping doesn't actually work. Maybe that is true, but some interviews I have seen with the EG4 CEO say otherwise. So maybe is out promoting functionality that doesn't actually exist in his product or he needs to educate his team on how to set this up.
One problem he claims to have solved is the "dark start problem". That means if the grid is down and your batteries get low, they shut the inverters off to prevent draining the batteries completely. When the sun comes up you can restart your inverters, power your loads. The grid tied inverters should come on and allow the hybrid inverters to store the excess power in the batteries.
The problem is that you have to power up the whole house to get the grid tied inverters working. The Grid Boss, Flex Boss combo, can get things started more efficiently. They put the Grid tied inverters on the "Loads Terminals" of the Flex Boss. The Flex Boss hooks to the Grid Boss using the "Grid Terminals". When the batteries get too low, they disconnect the Grid Boss from the Flex Boss(es). The Flex Boss will actually continue to operate over night. It will only use a small amount of power. When the sun comes up, the grid tied inverters will start pushing power to the Flex Boss. Once the batteries are charged up enough the Grid Boss will connect them back to the loads.
So you should probably try moving your grid tied inverters to your Flex Box Load Terminals.
One of things about AC Coupled is that they need to manage excess power. This can be done either by just disconnecting the grid tied panels or using frequency shifting curtailment. Looking at the settings on this thread. AC Couple start means how drained should the batteries be before starting AC Coupling. I saw 30%. That means it won't turn on until the batteries are below 30%. So more reasonable figures might be on at 85 and off at 95.
AC Coupled doesn't work that well for Off Grid, but it will limp through an emergency grid down situation and prevent you from being without power. You do need to test it out and tweak the settings.
Unfortunately, very few people really understand it and have actually made it work.
When your system is connected to the grid and you are using grid tied inverters, you are simply operating the system in pass through mode. Your grid tied inverters are directly connected to the grid. This is not really AC coupling because your Hybrid inverters are not interacting with your grid tied inverters. If you have DC Coupled solar, that will work whether or not you are off grid. The DC flows to the DC bus. There it can either charge the batteries or be converted to AC and consumed or exported.
AC Coupled means that power can flow from your grid tied inverters to your loads. Your hybrid inverters will also be connected to your loads. Depending on your loads and your PV production, your hybrid inverters will either make up the needed power for the loads or store the excess power in the batteries.
In addition an AC Coupled system needs to insure that the batteries don't become over charged. Some systems do this by just cycling the grid tied inverters on and off. Others by using the frequency curtailment built into the grid tied inverters.
So to say that AC Coupling only works "when the grid is present" is to say AC Couping doesn't actually work. Maybe that is true, but some interviews I have seen with the EG4 CEO say otherwise. So maybe is out promoting functionality that doesn't actually exist in his product or he needs to educate his team on how to set this up.
One problem he claims to have solved is the "dark start problem". That means if the grid is down and your batteries get low, they shut the inverters off to prevent draining the batteries completely. When the sun comes up you can restart your inverters, power your loads. The grid tied inverters should come on and allow the hybrid inverters to store the excess power in the batteries.
The problem is that you have to power up the whole house to get the grid tied inverters working. The Grid Boss, Flex Boss combo, can get things started more efficiently. They put the Grid tied inverters on the "Loads Terminals" of the Flex Boss. The Flex Boss hooks to the Grid Boss using the "Grid Terminals". When the batteries get too low, they disconnect the Grid Boss from the Flex Boss(es). The Flex Boss will actually continue to operate over night. It will only use a small amount of power. When the sun comes up, the grid tied inverters will start pushing power to the Flex Boss. Once the batteries are charged up enough the Grid Boss will connect them back to the loads.
So you should probably try moving your grid tied inverters to your Flex Box Load Terminals.
One of things about AC Coupled is that they need to manage excess power. This can be done either by just disconnecting the grid tied panels or using frequency shifting curtailment. Looking at the settings on this thread. AC Couple start means how drained should the batteries be before starting AC Coupling. I saw 30%. That means it won't turn on until the batteries are below 30%. So more reasonable figures might be on at 85 and off at 95.
AC Coupled doesn't work that well for Off Grid, but it will limp through an emergency grid down situation and prevent you from being without power. You do need to test it out and tweak the settings.
Unfortunately, very few people really understand it and have actually made it work.
skimandan
New guy
Is anyone feeding their FlexBoss21 max solar input?
The manual and specs place limits PER MPPT at 26A/26A/15A at less than 600VOC. 25kW max panels, 21kW max utilized.
The String Sizer tool adds per MPPT wattage limits of 9360W/9360W/5400W.
I currently have a 10s2p string rated at 9100 watts that I have seen go as high as 9250 due to cloud edge.
I am considering moving some panels to this string to create a 12s2p string that would have 550 VOC max at cold temp and rated output would be 10,920W. Any thoughts if this would cause problems or clipping? Its odd that the string sizer tool has the per MPPT limit but it not listed anywhere in the manual. Who am I kidding, I'm talking about EG4 documentation. Its not odd at all.
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