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magicpants avatar image
magicpants asked

Vic Multiplus II - Strange grid behavior

Hi everyone,


Im new here and had my system (Multiplus II, 2*Pylontech 3000c, 8*400w Panels) installed about a month ago. I have questions.


While using the VRM portal I have noticed something strange happening in the "grid" block on the dashboard. The values there would constantly fluctuate between -100w and about 80w. This happens all the time. The historical values indicated 0w sent to grid and about 1kwh pulled from the grid every day. This system should not send anything to the grid and only pull from the grid when batteries reach 20%, which hasn't happened yet. Grid set point is 0w.


What does the negative values mean on the dashboard and why is the inverter still importing power from the grid when the batteries are charged and solar output is available ?


Many Thanks

MP





Multiplus-II
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2 Answers
seb71 avatar image
seb71 answered ·

You will have that fluctuation (in/out the grid) especially when there are sudden changes on loads.

Negative values mean feed in into the grid. Positive values mean you take energy from the grid.


Those ranges (-100W...80W) do seem large. Do you have some large load that is turned on/off frequently?


When you take 1kWh from grid per day what is the total consumption on the same day (from grid and solar/batteries)?


Which ESS mode do you use?

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magicpants avatar image magicpants commented ·

Thank you for your reply.


The fact that the inverter feeds into the grid is concerning. It is not allowed where I am. However, the historical values indicate that nothing has EVER been pushed to the grid.


The largest load (AC Loads) is about 800w (poolpump) that switches on at 10am and switches of at 3pm.


From the Dashboard for yesterday:

To Grid: 0 kwh

From Grid: 0.7 kwh

Production: 14 kwh

Consumption: 13 kwh


ESS: Optimized (With Battery Life)


Thank you :)

EDIT: Posted as answer and not a comment. Deleted previous post.

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Warwick Bruce Chapman avatar image
Warwick Bruce Chapman answered ·

This is as a result of your set-point being at 0W. Push it up to 150W and see whether the negative values stop.


At 0W, the system has the impossible task of tying to hold the grid at zero but fluctuations in load and PV power make that practically impossible. If you want a low grid set-point and your grid can tolerate the momentary negative values, leave it as is.


If you want to be absolutely certain you never export, then push your set-point up accordingly.

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