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brianor avatar image
brianor asked

ESS and Freedom Won Battery

I have been working through a number of threads to find a solution to the draining of Freedom Won battery prior to being fully charged by PV, where loads in excess of PV supply is sourced from battery (and not grid).


My system setup as follows:

MultiPlus II 48/5000

Victron MPPT 150/85 Te VE-Can

Cerbo GX

FreedomWon 10/8 (200Ah)

Lynx Power In

3.2kWp PV (3x3)


I have set battery SoC to 60% with an aim to use 40% during night to feed critical loads. I have noticed two issues though:

  1. The battery supplies power to both critical and non-critical loads, which causes it to drain too fast.
  2. During the day while battery is charging via PV, it keeps on using battery power for loads prior to being fully charged. This slows down charging and often does not reach 100% at end of day.


I suspect this is an ESS setting that I am missing. Any advice?


Thanks

ESS
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2 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

For me it sounds like the normal behaviour for a ESS.

Is the system on-grid or off-grid?
If on-grid are the non-critical loads connected to AC-IN or AC-OUT 2 and is there a grid-meter?

A wiring diagram of your system would be good.

As long as the grid is available both, critical and non-critical loads are supplied from the battery because AC OUT 1 and 2 are hard-wired together internally.
With an external grid-meter and phase-compensation enabled the system also uses the battery to reduce the energy usage from the grid.

Only surplus PV energy is used to charge the battery, first priority is to supply the loads.

If you want to use PV and battery only for critical loads you have to connect the non-critical loads to AC-IN and use the internal energy-meter of the MultiPlus.

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brianor avatar image brianor commented ·

Thanks Matthias

It is a grid-connected system, but not configured to feed-in excess to the grid.

All connections is made to AC-IN and AC-OUT 1 (AC-OUT 2 not used). Also using the ET112 grid-meter (single phase power). Assume phase compensation needs to be off in a single phase system?

Will work on wiring diagram.

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brianor avatar image brianor commented ·

Another observation - I noted from another forum thread that the AC Out 2 on MultiPlus is meant to connect your non-critical loads, and if there is grid failure the battery will only feed AC Out 1? If you say these two connections are hard-wired, how will the Multi distinguish between which loads to carry?

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Warwick Bruce Chapman avatar image Warwick Bruce Chapman brianor commented ·

There is a relay that opens (disconnects loads) on AC Out 2 when the grid goes away. That relay can be programmed to stay closed (loads connected) until some other condition is met eg. SoC reaches 60%.

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Warwick Bruce Chapman avatar image
Warwick Bruce Chapman answered ·

You don't have an energy meter. Disable feed in and then ESS will only support the essential loads.

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brianor avatar image brianor commented ·

I have an ET112 energy meter which appears in Cerbo device list.

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