Desperately needing generator to connect again. Off-grid, Easysolar, LG Chem. needs LOM disabled?

DIY
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Hey everyone,

I have been reading a lot of helpful stuff on all the victron pages, but this is the time I simply couldn’t find a solution to my problem and hence have to write this post and hope that somebody has an idea on how to help.

I have a victron easysolar 48/5000 (first generation) with a LG Resu 3.3 and a LG Resu 10 battery connected via an LG Resu plus. The system is completely off-grid - which I know, you’re not supposed to do - but its humming peacefully for nearly 7 years already in remote Portugal. I have no mains electricity, and also no Victron dealer that installed the system or that I can ask for help.
It’s completely off-grid and we installed everything ourselved according to Victron & LG Chem Resu [Victron Energy] years ago. I am absolutely thankful for that manual and we couln’t have made it without that one.

As it was very dark these last days, I wanted to get out the generator (small 3kw) and connect it to the AC in to fuel up the batteries a bit. I already did this last winter and it worked fine following the great tips on MultiPlus Generator FAQ [Victron Energy] and we were able to squeeze about steady 12A out of the generator.

So I wanted to repeat it this year, but somehow the generator kept disconnecting if we allowed current higher than 2.5 Amps. We checked all the settings, played around a long time, but couldn’t get it to work. So we thought something is wrong with the generator. We checked it by directly drawing energy from it and could easily get him above 12 Amps. Just when connected to the Victron, he always got disconnected above 2.5 Amps, even with no loads and the inverter set to “charge only”.

UPS is off, wide frequencies are accepted, Voltage window from 180 - 270, dynamic current limiter is on. Weak AC input is on. And the Voltage and Frequency seem absolutely stable when running under 2.5 Amps. Generator running calmly without stress.

Then, I stumbled across the grid setting, which we maybe had switched from “none” to “other” or to LOM enabled at some point. So now our theory is, that it is the LOM that need’s to be deactivated again. Problem is… we can’t.

The dilemma is the following:
We are in an off-grid system, so we could easily turn the grid code to “none”. BUT, we also need the ESS-assistant to run the LG batteries and the ESS-assistant does not allow deactivating the grid standard. And when we set the grid code to “other”, the ESS is happy, but then we cannot disable LOM detection because we have no grid code password that would allow us to turn it off.

I really hope you understand the situation and somebody has an idea or hint on what else to try. We had to turn the complete system off for several hours, to not drain our LG batteries and are completely without electricity/lights/internet for most of the day (and night anyhow). The weather forecast predicts no sun at all for the next four days and without the generator able to charge the batteries it will probably also stay dark for us for a while :frowning:

So that is the situation - I hope someone can help us!
Thanks a lot to everyone! Any ideas on how to turn LOM off or on what to try on the generator settings are welcome.

related bonus question:
Say I find an old configuration file with grid code still set to “other” and LOM disabled, could I write this one back onto the system without needing the password?

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The grid-code password is in the training manual. You can access it by completing the training on Victron Professional.

I wouldn’t use a generator as the “grid” input with ESS enabled — the MultiPlus can feed back into the generator.

You’re also using an unapproved MultiPlus in an off-grid setup, so this isn’t even close to the intended configuration.

I’d disable ESS entirely, set the input type to Generator, disable battery comms, and rely on the MultiPlus’ internal battery monitor — or install a shunt if you want more accurate monitoring.

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Hey Owen, thanks for your input!

The grid-code password is in the training manual. You can access it by completing the training on Victron Professional.

Good to know, I will look into that!

I wouldn’t use a generator as the “grid” input with ESS enabled — the MultiPlus can feed back into the generator.

Oh, I wasn’t aware of that! Still I don’t think this was causing the Easysolar to reject the generator when input is set higher than 2.5 Amps, right?

You’re also using an unapproved MultiPlus in an off-grid setup, so this isn’t even close to the intended configuration.

I am absolutely aware of that, but unfortunately there is nothing I can do about that now. It is what it is and it’s been running smoothly since day one and hope so for many more years.

I’d disable ESS entirely, set the input type to Generator, disable battery comms, and rely on the MultiPlus’ internal battery monitor — or install a shunt if you want more accurate monitoring.

As far as I understood Victron & LG Chem Resu [Victron Energy] , I HAVE to use ESS in order to keep the LG Batery alive. Without a proper signal from ESS, the LG BMS will shut down the battery after about 10 minutes. (which it really does, as we have experienced often, for example when data cables where missing)

Appreciate all the help a lot!

I disabled dynamic current limiter now in the config file (not much hope that it’ll change anything, but it’s the only other thing I haven’t tried). Will upload the file and test if hopefully midday, when the sun is able to send some rays through the thick clouds and I can turn the system on for a bit again….

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I think the best option if you want to struggle on is to look at a Quatro with an extra input for a generator. Maybe even look at getting another multiplus just to use as a charger. If you can keep the battery alive then it will have to take charge. You could set it up as a DC system supply and shunt. You will also have a spare multiplus. They are the cheapest option to charge 48V.

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I have some videos for you. Setting up an ESS Quatro for generator input.

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Hi Owen,

great, that sounds like a good idea for the near future. This would also provide better backup to my fragile setup. I will also have to get a stronger and more reliabale generator, I guess. Unfortunately all of that won’t help me to get through the next few days. As it is, we’re rained and flooded in with the road access nearly cut off so getting any kind of new equipment and installing it will have to wait for a week at least :sweat_smile:

I also just saw you uploaded some videos, which I will check later. Thanks!

7

This is very important. I run 3 ESS. All of them when they finish absorbtion will export full noise to the grid until the voltage drops to the float voltage. If you lose a battery the one still connected fills up you could export to the generator.

8

Can you try something for me? I am curious. What happens if you disconnect the MultiPlus from the Venus device and run it in ESS demo mode? Will that spoof the battery?

If that works, then maybe you could set the MultiPlus to run standalone in generator passthru and power assist with the ESS assistant removed. That will require a new config file.

Settings, general, down the bottom.

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Have you tried it yet? This is my test system and in demo mode with nothing connected the ESS assistant is running.

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Hi @flowman

You are so far off the “supported” configuration here that I can’t give you any advice sorry,

BUT I did want to clarify one of your assumptions;
When the LG chem battery was released there was no seperate and superceeding DVCC (distributed voltage and current control) system.

This came later, and took over many of the functions and controls that were first introduced for managed lithium batteries via ESS.

Victron never support LG batteries off grid, and don’t support them at all any more.

That said, the keep alive signal that you referred to, as does the documentation, is not an inherent part of ESS mode any more, and is now managed by turning on DVCC instead.

Once again as the disclaimer, I am not advising any of this configuration, just clarifying that presumption from some old documentation that hasn’t kept up with the firmware changes.

11

Hey Owen, sorry for taking a while coming back to you. I was busy helping a friend trying to get his generator to work (pretty similar setup, but no ESS since he has no LG batteries, hence no LOM). And we got it to work. So that was good. Also we had a bit of sun to take the pressure of the situation. Still turning off electricity at night.

Back to your question of trying disconnecting Venus from Multiplus. I have never done this, as I try to change as little as possible “inside” my Victron system. That’s pretty much why I have an EASYsolar :sweat_smile: in order to not worry about the elecrical inside of the system. I wouldn’t know how to do that and now is not the right time to start those kinds of experiments for me - “never change a running system”.

Next thing I’ll do is what Guy hinted on - Switching off ESS and replacing it with DVCC (which I was already thinking about trying a month ago, when I came across this feature). And this can be done via SW. Which comes in handy as I am an IT-guy and for sure no electrician :innocent: . If I succeed replacing ESS with DVCC and it’ll keep the batteries alive, I might be able to disable the grid altogether without having to worry about LOM. And if that doesn’t bring the generator power supply back, then I’ll have to go get a new generator as soon as transportation allows for it.

Again thanks a lot for your input!

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Yes, that makes sense. I really like DVCC.

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Hey Guy,

thanks for you honest words about the supported config. I am fully aware of that, but I still love my setup with your equipment :wink:

I will see how far I’ll get with DVCC, as I came across that feature anyhow a month ago, when we moved the solar panels and didn’t get more Solar Power in (as we would have expexted). Problem back then was, that we had limited the max charge current to 50 Amps seven years ago, cause that was the max input for the LG Battery stated back then. As now, we have two LG Batteries, we raised the limit to 80 and it works neatly and we’re getting a lot more solar power in.

I’ll go through the DVCC documentation later, but my understanding so far is:

with the “Max current setting” on the MPPT Charger I will define how many Amps will go from the Charger to the whole System (Inverter+loads and LG Batteries)

whereas the settings in the “limit charge current” in the DVCC settings will limit how much of that current will actually go into the batteries?

I am still confused a bit about the charger situation. As when we had the easysolar set to “charge only” it was charging the battery from solar whilst using a bit of energy itself. When we set it to “off”, the batteries still got charged but with no self-consumtion on the inverter/charger side. So as we understood the information we found about that, it’s that there is a “AC charger” in the multiplus which is independent of the mppt charger and whilst set to “off”, the mppt charger still charges the batteries. Correct? Another theory is that ESS just overrides the physical switch, but I don’t think that is the case here, as you see a drop in energy consumption when flicking the switch from “charger only” to “off”

So now, these DVCC settings regarding charge: Will they influence the multiplus charger, the mppt charger or both chargers?

Would be wonderful if one of you could explain the connection here.

Thanks so, so much!

14

Hey,

short update everyone:

  • DVCC activated succesfully
  • ESS assistant removed and uploaded config file succesfully
  • Battery still alive after one hour. No disconnection –> success
  • I can now limit power going into the whole system with MPPT “max charge current” setting
  • I can now limit power going into the RESU batteries with “limit charge current” setting in DVCC
  • I played around a bit with those two settings and it works perfectly

I am very pleased. The VRM portal still shows the ESS option (which I set to external control), but I read, that this might just be cached somewhere and might dissapear after a while.

Furthermore:

  • Removing the ESS assistant from the config file, I was also able to deactivate the grid (finally :slight_smile: )
  • That way, I also got rid of LOM without needing the grid password

The final test will now be to test if the generator stays connected. If not, then I don’t really know what the reason might be. To be on the safe side we also built a PE-N bridge.

Thanks for all your input, will keep you posted.

15

Hey guys,

BIG success! It seems like removing LOM/grid was the solution.

We got the generator staying connected very stable and were able to raise the generator current limit up to 8A without any problem. (Remember: before that he already got disconnected at 3A).

Also when turning on smaller loads, the generator handled these and stayed connected.

Just one thing keeps on puzzling us: Whatever we set the AC input limit to…..8, 9, 10, 11, 12, 13… the maximum input the generator reached was 7,x Amp. Never going above 8A as shown on the AC-Input statistics in the color control GX screen. We could raise it with the settings up to 7/8, but not beyond that. But knowing from last year, I reached 9/10 easily.

So first we thought it might be the generator just not wanting to provide more. But

  1. it’s a stupid generator without any limit and

  2. as soon as we added smaller loads like 300 Watts more, he would raise power output a few amps above 7A. So he actually still has more power in him.

Somehow it seems like the built-in charger from the inverter already maxes out somewhere below 7 Amps. But we didn’t find any setting for that, other than the “Generator current limit” (like its called in VRM), “Input current value” (like its called on the color control GX) and the “AC input current limit” (like it’s called in VEConfigure) [see screenshot. Maybe you could improve this, by actually naming it the same in all three situations :wink: ].

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Anyhow, so no matter how high we set that value, with low loads connected (like 150 watts) the AC-In L1 would never go above 7.5 A.

What could be limiting the multiplus charger here?

[other settings: no PE-N bridge, Dynamic current limiter and power assist off, Weak AC on, UPS off, lithium batteries ticked on, Battery type: no corresponding default, wide Freq/Voltage window]

Does the charge curve matter? the current there is set to 20A. Is that the limit? (20A x 55V = 1000 Watt // on AC input side: 7A x 230V = 1610W minus (loads at that time and self consumption and loss in inverting) is about 1200 W…pretty close….)

Any suggestions :slight_smile:

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What do you have DVCC set to? Here’s how it works: DVCC uses the MPPT first. So, for example, if you have 20 A of solar and DVCC is set to 30 A, the extra 10 A will come from the grid/generator. If you have DVCC set to 7 A and there’s no MPPT input, the internal charger will supply 7 A.

Does that make sense? Does it sound like what’s happening?

Also, in VE.Config, under the charger section, do you have 20 A set as the max charge? There are quite a few variables to check to see what’s actually going on.

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