Hi all,
I am trying to connect a generator to help charge the batteries on these dull days. This is an offgrid setup, Rosie, Barcelona, Evault Max Battery + Solar.
I have connected the genset and ran it up. The Rosie changed over to the Grid/Gen AC and runs the house AC but it is not charging the batteries. On the menu, if I go to GRID SUPPORT it is DISABLED. I can not enable it. It only stays in DISABLED and I think this is why it is not charging the batteries.
It has the latest software updates on all units.
Any ideas please?
Just to be sure, you need to have the charger turned on in the Rosie. Inverter Config, AC Input, Charger ... select off or on.
Dave
Quote from: Groton Vermont on November 01, 2025, 03:26:54 PMHi all,
I am trying to connect a generator to help charge the batteries on these dull days. This is an offgrid setup, Rosie, Barcelona, Evault Max Battery + Solar.
I have connected the genset and ran it up. The Rosie changed over to the Grid/Gen AC and runs the house AC but it is not charging the batteries. On the menu, if I go to GRID SUPPORT it is DISABLED. I can not enable it. It only stays in DISABLED and I think this is why it is not charging the batteries.
It has the latest software updates on all units.
Any ideas please?
I believe you have to place the Rosie in standby before you can adjust that setting.
As far as Grid Support, there is no 'enable' function. There are 4 choices under grid support, rotate the knob to select SOC, Battery V (voltage), Breaker, or disable. Depending on which option you choose, the other line selections below Grid Support become relevant.
Dave
The Charger is turned on.
To put the inverter into Standby I got USER/SYSTEM_FUNCTIONS/INVERTER ON/OFF and set to OFF... correct?
I tried this but still could not change the GRID SUPPORT Setting.
Jim
Thank you for your responses.
In the manual:
• Grid Support – Rosie uses grid AC for loads based on SOC % or Battery Voltage.
o SOC%:
▪ Low SOC % - Rosie uses AC IN (grid) to charge batts and run loads.
▪ High SOC % - Rosie disables AC IN and uses batt bank to run loads.
o Battery Voltage:
▪ LBX – Set to low Batt V setpoint.
▪ HBX – Set to high Batt V setpoint.
But I don't get this displayed, I get:
Grid Support DISABLED
Support Volts 54.4V
And even if the inverter is in Standby I still can not change the DISABLED
Jim
Quote from: Groton Vermont on November 01, 2025, 06:03:16 PMBut I don't get this displayed, I get:
Grid Support DISABLED
Support Volts 54.4V
Can you drop the support volts down? At 54.4V it seems like it would rarely be on battery?
Some issue with battey bms comms overriding?
The Grid Support was preset at 48.0V, it still wouldn't let me adjust the DISABLED and was not charging.
What does SUPPORT VOLTS mean, I read it as if it's below this value it would 'support' as in charge??
The battery and the inverter do not communicate.
While the generator was running the house ac, the charge controller was still charing the battery.
I can't see how the bms could pick a source, there is not that level of control.
I feel there may be a setting I have set that has disabled the changing of the DISABLED. Or else mine has a bug. But the softward upgrade process wouldn't allow a bug through I think, but idk....
When you move the cursor to disable, can you push the knob and highlight it, then turn the knob to select SOC/Battery V/Breaker?
I can highlight it but it doesn't change.
Unlike the voltage below when highlighted it can be changed.
May I suggest you watch this YouTube video by Midnite, talking about the grid and Rosie. 'Grid Curtailment Using the Midnite Rosie Inverter'. Perhaps it will answer some of your questions. I try to watch everything that Midnite posts dealing with the Rosie, even if it deals with a battery or something I don't own. It's amazing how many details I glean from these that fill in the blanks from the manuals, which are very outdated.
https://youtu.be/bHIJ0zD0z8I?si=YbcBmdadkI072pEy
Quote from: Groton Vermont on November 01, 2025, 09:54:53 PMI can highlight it but it doesn't change.
Unlike the voltage below when highlighted it can be changed.
A couple of things I've learned: when you update the Rosie & MNGP2, first do the MNGP2, then the Rosie. Once they come back online, I select reset to factory settings on the updated devices. Finally, shut down Rosie completely, battery power off. Then power on and load ALL your data back into the various menus. Don't forget to check the date/time in the MNGP2.
Is the inverter powered on completely before you try to set the Grid Support settings? Make sure the inverter is ON in the User menu. You mentioned you turn it OFF there. I've never turned off the inverter from that menu. If I want the inverter off, I shut down the battery breaker.
Dave
"GRID SUPPORT" is not available in AC INPUT MODE = GENERATOR
Grid Support uses battery power to support incoming AC Power from the Grid and/or reduce it to about 300 watts incoming. This mode "pushes" current back at the AC INPUT and generators tend to get upset if this happens.
I have suggested a "Generator Support" Mode to use battery power to assist running loads that exceed the generators' output capability but I'm told that's a whole new bunch of code work so don't expect it any time soon.
Rosie is picky about some brands of generators, Cumins/Onan is one it does not like and refuses to connect & charge. Rosie says NOPE to my Onan 3500 in my RV.
Press "AC BUTTON" and check "GENERATOR STATUS" for volts and hertz within the settings.
Be sure to set BREAKER SIZE to just a bit less than the output available from your generator.
If feeding just 120V into L1 on Rosie set to half of that.
Rosie will only charge if there is any power left after powering the loads...
Hi, thank you for the reply.
Gen is 6kW so breaker set to 23A
Generator Status:
State Running 0:02:28
Start Manual
Stop No Reason
239V 60.0Hz
Input 2.4 kW
Charge 0 W
Load 2.3 kW
So it is passing through but not charging?
Jim
What is your battery voltage? Maybe they are fully charged?
Battery was at 22% SOC, not fully charged at all and the Barcelona was in Bulk, which you would expect.
Quote from: Wizbandit on November 02, 2025, 07:38:14 AMI have suggested a "Generator Support" Mode to use battery power to assist running loads that exceed the generators' output capability but I'm told that's a whole new bunch of code work so don't expect it any time soon.
I just would like to say that I believe a "GENERATOR SUPPORT" Mode would be a really great thing to add and for offgridders like me, it would be a game changer. I don't know any other inverter that has this. It would effectively allow any sized generator to be utilized, even just a 2kW unit. It would power loads and charge the batteries all at once (I assume).
If they already have the Grid Support code, to add Generator Support shouldn't be a great issue I'd have thought (I am an embedded systems programmer).
My 2p worth :)
Quote from: Groton Vermont on November 03, 2025, 10:30:50 AMQuote from: Wizbandit on November 02, 2025, 07:38:14 AMI have suggested a "Generator Support" Mode to use battery power to assist running loads that exceed the generators' output capability but I'm told that's a whole new bunch of code work so don't expect it any time soon.
I just would like to say that I believe a "GENERATOR SUPPORT" Mode would be a really great thing to add and for offgridders like me, it would be a game changer. I don't know any other inverter that has this. It would effectively allow any sized generator to be utilized, even just a 2kW unit. It would power loads and charge the batteries all at once (I assume).
If they already have the Grid Support code, to add Generator Support shouldn't be a great issue I'd have thought (I am an embedded systems programmer).
My 2p worth :)
You CAN power your loads and charge the batteries at the same time, done it on many occasions, just you can't have AUTOMATIC generator control, have to do it manually. You just can't do it in Generator mode. The Generator mode provided wider parameters for voltage, frequency, etc., but a descent generator shouldn't have any problems with tighter numbers. Just toggle between grid and gen to see the parameters it will allow. I have utility power connected, but don't power my loads with it very much, use batteries mostly and charge them daily with a Hawkes Bay Controller. I run my AC IN thru a ON-OFF-ON switch, up for utility and down for generator input. On a cloudy day, I either connect my Honda EU2000 or Honda EU3000 gen to the outside plug, throw my switch to the gen position, and fire it up. Just adjust the Breaker size down to fit the generator, as Wizbandit said, and you are good. I do this on a monthly basis just to exercise the generators and to keep the process fresh in my mind if really needed. Note my generators are 120V, but the Rosie handles it w/no issues. :)
Dave
"Charge" report is busted in that menu, opps...
Quote from: Groton Vermont on November 02, 2025, 12:20:07 PMHi, thank you for the reply.
Gen is 6kW so breaker set to 23A
Generator Status:
State Running 0:02:28
Start Manual
Stop No Reason
239V 60.0Hz
Input 2.4 kW
Charge 0 W
Load 2.3 kW
So it is passing through but not charging?
Jim
Quote from: aaapilot on November 03, 2025, 04:09:11 PMYou CAN power your loads and charge the batteries at the same time, done it on many occasions, just you can't have AUTOMATIC generator control, have to do it manually.
Hi Dave, Yes, I understand this. I am refering to having a load sharing between the generator and the inverter. If you had a 2kW generator and suddenly a 4Kw water heater switched on, I think the generator would kick off with an overload. Where as if the inverter could pick up the slack so the generator never exceeds the maximum load. Is that possible? So also, when there is just 200mA Load the generator could still run at full load, the difference going to charge the batteries.
Is this even possible?
Note, even with the "0 Charge" not working, the generator was not charging the batteries but was powering the loads. Does that mean Rosie didn't like the generator so did not allow battery charging but did allow load powering or is there still something else going on?
Thanks all,
Jim