Thanks for the glimmer of hope. I'll be looking for a way to log the frequency changes, but not sure if it's possible on this equipment.
My First Grid Down Simulation - EG4 18Kpv - No Way to Maximize Use of AC-Coupled Solar Power?
- Thread starter skoshorek
- Start date
Which inverter would be most likely to be able to log the frequency, the EG4 or the Delta grid-tied inverter?
I log my frequency with an iotawatt.
However, my grid tie inverter also shows the frequency and I can see the data in solar assistant.
Id be surprised though if the 18kpv doesn't have this data
sunshine_eggo
Happy Breffast!
Luxpower_Gilbert
Luxpert @Luxpower USA Team
ac couple must be connected to the generator input. and use ac couple setting under charge settings. Ac couple start (95%) and end (100%) must at least 5% gap difference. if you don't like to discharge your battery, use charge first (pv) settings.
Thanks for checking on this for me. Now that I know the EG4 18Kpv CAN do it, I only have to figure out WHERE it's hidden and HOW to unlock it. Your red circle on the grid icon is my first clue. I'll start by trying to poke on that icon a little bit. Once again, the members on this forum have come to the rescue.
It took me awhile, but I finally got through some of the other posts' suggestions, and I wanted to come back and thank you for your feedback. I was not fully aware of how the AC-coupling control system works, and knowing that other equipment has similar limitations is valuable. It also led me to investigating whether my specific grid-tied inverter will respond to incremental changes in frequency from the EG4 18Kpv. Forum member 1201 has given me enough feedback to point me in the right direction on that score. In truth, the system is working well enough that for the infrequent short grid-down events, and even extended outages, the batteries and solar are working together to keep the batteries nearly charged most of the day. The EG4 inverter just makes them take turns handling the loads when near full charge on the batteries. As a retired mechanical engineer, I'm usually looking for the most I can get out of a system. I'm getting closer to understanding what "the most" IS for my specific equipment.
Thanks for replying Gilbert. I have battery priority set on (in the android app), which I assume is the same as Charge First (PV) on the LCD screen settings. This illustrates one of my problems. There is not a one-to-one mapping of the settings in the android app with those available on the inverter's LCD screen. They sometimes have different names, and one, the AC Couple switch, will sometimes show OFF in the app while the AC Couple setting on the LCD screen always shows ON. This may be only an issue with the EG4 versions of the app and LCD screen software. Does the Luxpower software operate differently?
That being said, I have tried to set the start and stop setting for charging and discharging the batteries as close together as the software will allow for the grid up situation, while setting the low end for discharging batteries (while off-grid) at 48V to allow the battery bank to do its job with the grid down. The closest together the software will allow me to set the start and stop AC Charge setting is 52V and 57V (8.77% gap) for Voltage control, and 90% and 100% (10% gap) for SOC% control. The AC Couple start and end I have set at 56V and 57V, which is less than the 5% gap you have mentioned. The software will allow me to set them at 56.9V and 57V (.175% gap), and I might try that later. The AC Couple start and end can be set at 99% and 100% if I'm using SOC% for control. That's only 1% gap. I'm not sure what the difference is between AC Charge and AC Couple (also AC). Maybe the AC Charge settings are only for grid charging. Can you explain the difference, and if the AC Charge settings are operable when only AC coupling is active (grid down)?
Luxpower_Gilbert
Luxpert @Luxpower USA Team
Make sure you have the latest inverter firmware and lcd update. 18kpv and Lux 12k operate the same way…
If the inverter is connected to the grid the export to grid must be enable and 0.1kw is minimum to make ac couple to work this will turn on the generator input relay on to power your ac couple system.
The ac couple settings only take place when the grid is down or off-grid mode. Setting up the START and END to closely for ac couple will make the gen input relay on and off frequently and it will wear out fast..the END is when the ac couple will turn off (ac couple system) the Gen Relay and frequency shifting will start to works to prevent the battery from overcharging. START is when the generator relay will turn on again to provide power for the load and charge.
AC charge is for grid chargingonly, but if you want to support the load and charge the battery first with ac couple You must enable and set it to 0.1kw…
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yes my system is not connected to the grid yet which is why it throttles so heavily after the battery is full. when i connect to the grid it will just export any excess production to the grid
my pleasure. you are right - there is a lot of help on this forum.
I am at build fAAB-1312. I tried to do an update from the Android app yesterday, and I had three .hex files ready to go. When I hit the connect and update button I got an error message that it couldn't find the correct file (Not those exact words). I am thinking this is because maybe none of the files I had downloaded were newer than the build I already have. I wish the programmers would use more detailed, informative, error messages, like maybe "you already have the latest firmware installed", or "there are no newer files in your update list".
I wasn't aware that the AC Couple settings in the mobile app are only for grid-down. Good to know. I have the START and END settings close together to use the maximum amount of solar power during the day, and to have the batteries fully charged when the sun goes down. Is there any better way to make that happen? Why would I ever want to END the AC-Coupling for load support during the day? Sunshine is free. I'm not being a wiseguy. I want the solar power used for loads as the default, whenever it's available (for grid-up and for grid-down), and the batteries only discharged when there is no other power source available (at night or on a cloudy day with grid down). Some of the forum members have informed me that some grid-tied inverters may not be amenable to partial throttling commands from the EG4 18Kpv (for grid-down). I've been unsuccessfully trying to determine if my Delta M8-TL-US inverter can do partial throttling. What START and END settings would you suggest to minimize daytime battery usage and maximize daytime solar usage, but not overwork the relays? Is that the 5% gap value you mentioned before? I don't want my pursuit of the "perfect" (max solar use) to jeopardize the "good" (not wearing out my relays).
Not sure what you are saying. (EDITED at 22:29 Eastern: I think you mean to have AC-Couple on the LCD checked ON, Export to Grid ON, and Max Export Power set to a minimum of .1 kW when grid is up. I have Export to Grid On and Max Export Power set at 12kW, even though my system won't export that much) I have AC Charge ON and AC Charge Power set at 12kW. I have AC Couple ON and there is no kW setting for that. What I would prefer (with grid-up) is for AC-coupled solar to support loads first and charge batteries with any excess solar power. If the solar power isn't adequate to achieve 12kW battery charging (this will always be the case with my ~8kW solar array) then the grid would kick in the remainder of the 12kW of battery charging and/or load support. This will get the batteries back to full charge in the fastest possible time. My system appeared to operate this way this morning when I ended my five day grid-down simulation. The grid power and AC-coupled power worked together to achieve the 11+ kW of battery charging and also cover the minimal house loads. I agree that AC Charge is only for when grid is up, but it is not for battery charging using ONLY grid power; at least not the way it worked this morning. The 12kW power level for AC Charge was achieved by BOTH utility and AC-coupled power sources working in tandem. I was watching the LCD screen as it was happening. Was I hallucinating? (always a possibility at my age)
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I have already replied to this post in detail, but I have another question for you.
What is the latest inverter firmware for the EG4 18Kpv? Where is the best place to download it from? When you say they "operate the same way" do you mean they use the same firmware? I'm at build fAAB-1312 and LCD firmware v13.0.
By the way, I have talked to Signature Solar support about updating my firmware, and they surprised me by saying that they don't recommend changing the firmware from what it is shipped with, and that it's not required. What? I didn't argue the point, but went ahead with an update several weeks ago anyway. I hope it was just the tech I happened to be talking to that day, but I was floored by her comment.
@skoshorek just thinking out loud here- how difficult or easy would it be to switch the pv from the Delta inverter to the 18k pv . Is this an option?
Luxpower_Gilbert
Luxpert @Luxpower USA Team
EG4 latest firmware is 1312 and lcd is v13..
Like i said the ac couple setting about Start and End Soc is only take place when the grid is down or in offgrid application. This will protect the battery from overcharging. It will shut down the ac couple when it reach the END SOC, the ac couple will turn ON again when the battery SOC drop to START SOC. When theres a grid the ac couple will always be ON.
With my test i have successfully set my END SOC at 100% and START SOC at 95%. You need to remember the ac couple power must go somewhere or disconnect during grid outage to prevent blowing the battery and inverter..
If you don’t want to grid charge but you want to use the ac couple to support load and charge the battery at the same time the trick is to enable ac charge and set it to the lowest 0.1kw…
Luxpower_Gilbert
Luxpert @Luxpower USA Team
We do that recommended updating the inverter if everything are working but in this case if your build firmware is less than 1010, and you want ac couple with frequency shifting, you must update to the latest firmware available.
If you don’t mine DM your Inverter SN or Dongle Sn?
You should check the grid setting on the Delta first. No point testing further until it's setup to with the appropriate grid code for frequency-watt curtailment. The typical default is UL1741 (2015) which only supports on/off and no frequency-watt curtailment.
The EG4 version of the Android app will not allow using the SOC% START or END settings at all. They are greyed out, and I don't know why. I can only use voltage control. I'll set the END to 57V and the START to 54.1V (57 x .95) for grid down situations.
Can I still use Quick Charge if I have the AC Charge Power set at .1kW, or is the power limit going to affect Quick Charge as well as the normal AC Charge?
Luxpower_Gilbert
Luxpert @Luxpower USA Team
are you using closed communication between the inverter and battery? If yes change your batt charge control to SOC instead of VOLT. If not set END 1volt lower than you battery spec charge voltage and for START set 2 volts lower than the END voltage..
Since you’ll be using the app to activate then you can manually set the power limit that you desired unless you want to charge the battery with grid then set the power limit to whatever you like…
I'll try these suggestions. I'm using the EG4 battery hub which is communicating with the inverter. I tried setting the AC Charge control back to SOC%, but the SOC% settings for AC Coupling stayed greyed out. I'll try the alternate settings method later. EDITED 1/8/24: I now see that the DISCHARGE control setting is the one that determines the AC Couple settings.
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