Grid input settings ignored

Q&A and troubleshooting
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1

I had a great Victron/Pylontech system (DC coupled) installed in May. But it’s never behaved as I want it to.

I have 25 panels; Multiplus II 10000; 3 x Victron MPPTs ; Cerbo GX; 6 x Plylontech US5000s; Victron grid meter.

I want the system to prioritise PV and only use the grid as a last resort if there’s no PV and the min. SOC has been reached. If this is the case, I want a maximum of 500W to be sent to the load (and battery if load is < 500W).

Is this asking too much? I ask because the system ignores grid current and set point settings. The only way to control grid import is to set the battery input current to 10A (it’s a 50V system) and this would limit PV charging.

It also does crazy things like exports to the grid when I don’t want it to. I’ve tried researching and using AI chat services. But the installer and my research has turned up with no results.

What I have to do now is turn the grid off manually and, if I want it on, set the battery input current to 10A.

But I want the system to handle this without me having to manually intervene.

Does anyone know what’s likely to be wrong?

2

Hi did you try to set it up as ess? Thats should do what you want, first power from pv, if needed from battery and with to high loads or low soc use grid

One thing, ess needs grid to balance so there will always be a small amount of power used from and to grid

But what do you mean with:

3

Thanks Marc

I’m not sure what’s involved in setting up ESS. ESS was configured by the installers and I have tried altering various settings. Maybe there are menus and settings I don’t have access to.

Regards. Stanton.

4

I mean that I have set our contracted power with our grid supplier to 500W - just to cover overnight loads and some marginal battery charging. So, if the Victron system does not comply with this 500W draw from the grid, the grid switch will trip. I’m able to change settings fairly confidently but it seems our system is not configured well. I don’t know what other settings and physical issues might be causing problems. As I say, changing grid limit parameters seems to have no effect because our batteries just draw what they want. The only way I can control this is to restrict the battery input current limit to 10A I.e 500W for a 50V battery system.

5

I think you will have to share all your settings/screenshots to be able to find out what the problem is

6

A setpoint isn’t a hard limit, it is a point that the system tries to balance the load, it will ebb and flow around the setpoint as loads vary.
500W is unrealistic, you can’t even set the AC input limit that low.
Your only real choice is to use automation to disconnect AC in under specific conditions (time of day, load etc) and have it reconnect as necessary, but you will struggle to prevent the system from never exceeding 500W.

7

Thanks for that. Yes, I think having more explicit control via automation is the way forward.

Is it a big deal to use something like Home Automation with the system. I plan to look into that in the future.

Regards. Stanton.

8

Nodered is in the large venus image. Really straightforward to use it for control.

9

Do i understand it correctly that you have a 500w grid limit from your supplier and a device to cut off when you exceed that?

If so, then as Nick stated, setpoint will not work like you would want to for that specific use case

10

Thanks, both. It seems I am asking too much - I’m surprised. I thought I’d be able to have the grid on but only used to cover loads when the battery was at min. SOC and no PV.

I will look into Node Red and Home Automation at some point.

Thanks again.

11

You can do that, but if your grid is limited to 500w that would be a challenge

maybe take look at the ESS documentation to understand better how it works or can be configured?

12

There is a walkthrough manual here for victron and pylontec ESS set up here.

Then you set your mind soc in ess on the GX menu- basics done

This is done in dvcc so you do have some access to settings

13

Thanks very much.