Help with DC excess exporting/feed-in

DIY
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1

Hi community,

I’m hoping someone can help me with what I also hope is a setup issue.

I have a ~4kWp PV array going to a Smartsolar 250/70 throguh a Lynx bus to my batteries and MultiPlus-II 10kVA.

I also have a ~5kWp PV array going to a Solis 5kW inverter, into the MultiPlus-II.

This is all controlled by a Cerbo

All seems to work as expected except for one scenario (may be broader than this, but its most evident here).

When my battery is full, and I’m using less than my AC coupled array is generating, my DC coupled array does not export. It drops to effectively 0W.

Below is a screenshot of this - which is a consistent state, not some momentary thing. I’ve observed this over mulitple occasions, so its readily reproducible.

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Here are what seem like relevant settings:

My grid setpoint is set to -50W

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If i set the Grid Setpoint to some large, negative number like - 7000W, then the battery starts discharging and the DC PV array starts contributing as much as the weather permits.

Can anyone help me here?

Thanks

2

Hi Andrew,

your settings seem to be ok. At least the shown settings are not different then mine… Besides the peak-shaving. This it not activated in my system.

The grid setpoint should be also fine, if you change it further down, then the PV charger as well as the battery will try to deliver this limit. Also during night, so this ist not the solution here.

Can you show us the ESS settings (the ESS main page)?

And what is controlling your Multiplus? There it says “External control”, but I don’t see a voltage in the battery symbol, so is there a connection between your battery to the Victron system? Maybe there is some conflict regarding the Multiplus control from battery side…

3

Turned out to be a DVCC setting, the charger was conflicting with the BMS and shutting off instead of continuing to export