Grid First

Hi all,

I have a MultiPlus-II GX 48|5000|70 and solar feeding the house and charging my 15,4 KWh BYD battery using ESS.

In summertime all power comes from the battery/solar, if needed, extra power comes from the grid.

During winter times, I like to do it the other way around. Use the grid to feed the house but with a limit of 2.500W. Extra power should come from the battery.

Is this even possible? Node-Red?

Thanks.

It is possible through the GX.
Input current limit 2500w ÷ grid voltage

Set batteries min SOC higher and set peak shaving either up to thet limit or allow small draws under it.
How much of your load is above 2500w? How long is the load above that?

Last night just above 2.500W.

During the day it’s never a problem but at night I charge the battery untill a certain level depending on the forecast.

When the load goes above 2.500W I switch to ESS which stops the charging of course. Beter would be to keep feeding the house from the grid, with some extra power from the battery untill the load goes below 2.500W again.

Make sense?

It took me a while to figure this out.
Now at night I set ESS mode to “Keep batteries charged” and limit the charge current in DVCC.
That way, when I reach 2.500W or more, charging stops but I can still use the grid.

What you suggested was “Limit system feed-in” in ESS.
Should work the same way except when the load goes above the Multiplus limit, what then?

In the end the solution was very simple.
While charging overnight, I set ESS to “Keep Batteries Charged”, and calculate the maximum current.
When the load goes above 2.500W, I go back to “Optimized without battery life” and set the Grid Setpoint to 2.500W.