'Off-Grid' meets 'Grid' - Sort Of - SkyBox Installed ? ** victron ESS Dilemma**

[Consumerbot3418]

Thanks for your reply 3418,

Yes, my AC-Coupled setup is just a pre-existing system in parallel on the AC-In of the Multiplus.... and just feeds the house loads, then exports all excess (5kW Max Export here in Australia). I notice this AC-Coupled PV Inverter does assist with the Critical Loads AC-Out_1 of the Multiplus during high loads, but only until the Battery / Inverter catches up, or batts drain to the minimum SoC... this PV excess and grid then takes over all those loads.

The Multiplus manages to maintain a very close Zero Export/Import at the grid point (ET-112 Meter) when the AC-Coupled PV Excess is assisting the charging of the battery's in partnership with the DC-Coupled PV first thing in the morning. (See PV/Load curve pic)

I just cannot seem to get the Multiplus to feed back the other way at all to assist with the house loads. Sorry for mis-understanding @Consumerbot3418 but the Multiplus is manually set to "ON" which I understand is Invert & Charge. Within the Cerbo it is also activated (see setting pics). Also I've attached a current (right now) Screen Shot whilst at night time with no PV that illustrates the Multiplus not helping the loads at all, even when the loads are small and the grid Setpoint set to varying numbers between -50 to -500 Watts. Thoughts ?

Hm, it looks like it just doesn’t want to invert… the question is “why?”

I’m guessing that the “self consumption from battery” setting is related to your external meter, as I don’t have that option on my setup.

Again, I don’t have any experience with external metering. If it was my own system, I might be tempted to change the grid metering setting to inverter/charger, and see what changes, if anything. And maybe the other setting mentioned above.

As already mentioned, the grid code stands out as a possible culprit.

If not that, it must be another config issue, and the external metering makes it even more challenging for me to help, since I haven’t any experience, and can’t see or test behavior myself.

I also don’t use BMS communication/DVCC, so that’s yet another confounding variable.

But this is a separate issue and I dont' want to muddy the waters ?

Good idea! ? It may actually be related, though…

 

[Snapperhead]

Hm, it looks like it just doesn’t want to invert… the question is “why?”

I’m guessing that the “self consumption from battery” setting is related to your external meter, as I don’t have that option on my setup.

Again, I don’t have any experience with external metering. If it was my own system, I might be tempted to change the grid metering setting to inverter/charger, and see what changes, if anything. And maybe the other setting mentioned above.

As already mentioned, the grid code stands out as a possible culprit.

If not that, it must be another config issue, and the external metering makes it even more challenging for me to help, since I haven’t any experience, and can’t see or test behavior myself.

I also don’t use BMS communication/DVCC, so that’s yet another confounding variable.


Good idea! ? It may actually be related

You’re correct…. I just nailed it with a change in grid code. It’s doing exactly what it is supposed to now with respect to it’s parameters within the ESS environment. Finally ! From here it’s just testing and tweaking to get all the variables playing nicely together to get me through the night until the PV wakes up and then more testing and and tweaking ?
Definitely highlighted the need for some more battery’s, as if 200Ah was ever going. to be enough ?! Haha Thanks lots to both you and the Mighty Eggo @sunshine_eggo for helping me look outside the box ????

 

[Consumerbot3418]

You’re correct…. I just nailed it with a change in grid code

That’s great to hear! Thanks for coming back to share the resolution with us.

200ah at 48V ought to be enough to keep the fridge running and the lights on overnight in a grid outage. Exactly how comfortable you want to be will determine how much more battery you’ll need to add. I’ve got about 15kWh of LFP, and it’s enough for our whole house overnight, including multiple freezers and AC in the bedrooms, if not extreme weather. That’s assuming it was fully charged, though. A string of cloudy/rainy/snowy(!) days is tough to get through, though.

Anyway, I’m sharing in your pleasure at seeing your investment actually doing what it was meant to do! ?

Point me to your generator thread on the Victron community forum? It’s possible to change the AC1 input from grid to generator, and at that point, it should grab as much power as it can to charge the batteries, and also avoid backfeeding. I’m working on a way to automate that in my case. Having a Quattro would simplify matters, but… $$$$!

 

[Snapperhead]

That’s great to hear! Thanks for coming back to share the resolution with us.

200ah at 48V ought to be enough to keep the fridge running and the lights on overnight in a grid outage. Exactly how comfortable you want to be will determine how much more battery you’ll need to add. I’ve got about 15kW of LFP, and it’s enough for our whole house overnight, including multiple freezers and AC in the bedrooms, if not extreme weather. That’s assuming it was fully charged, though. A string of cloudy/rainy/snowy(!) days is tough to get through, though.

Anyway, I’m sharing in your pleasure at seeing your investment actually doing what it was meant to do! ?

Point me to your generator thread on the Victron community forum? It’s possible to change the AC1 input from grid to generator, and at that point, it should grab as much power as it can to charge the batteries, and also avoid backfeeding. I’m working on a way to automate that in my case. Having a Quattro would simplify matters, but… $$$$!

Thanks ?? I’ve got my eyes on a pair of the new Jakiper 230Ah rack mounted 48v LiFePo4 units…. They reviewed really well by ‘Andy’s off grid Garage’ here in Oz

That should provide me with a few days of zero sunshine up here in the mountain fog ?

I have mostly hijacked someone else’s post in my search for generator solutions…. But am yet to test it (and LOM) with the new grid code…… So watch this space ??? I’ll start another thread here probably.

Thanks again ??