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flenis avatar image
flenis asked

Grid feed-in appears throttled though it's enabled

I have a grid-tied, DC-coupled 3-phase system with Multiplus-IIs, running with ESS.

My issue is that the system seems to throttle solar production rather than feeding in excess.

I have been running it with feed-in disabled for good while but I'm now approved for feed-in and so have changed the settings in the Cerbo.

Grid setpoint is normally at 0W but the other day, the battery was around 98% and just taking a trickle, sun was shining and when I changed the setpoint to about -500W, the solar production immediately ramped up. No scheduled charging active.

Any ideas of what might cause this throttling?

Could it be firmware-related?


DC-coupled PV - Feed in excess is enabled.

Feed-in limiting is off

Charger and Inverter power are not limited.

Multiphase regulation is set to total of all phases.

ESS Mode is Optimized (without BatteryLife)

Standard european grid code is selected.


3x Multiplus-II 48/3000 in 3-phase configuration, Firmware version 501

1x Smartsolar MPPT 450/100 and 2.4 kWp of solar panels. Firmware 1.11

Cerbo GX running firmware 3.00

SmartShunt

10 kWh stack of Leaf batteries, 14s

Multiplus-IIESS
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Alexandra avatar image Alexandra ♦ commented ·

@Flenis

Reboot the whole system.

Shut it all off including the inverter and restart it up again.

Sometimes feedback with 95% SOC incase of grid faliure works better you might need to experiment there. The fact that you have a shunt -does that mean that the leaf batteries have no comms to the system?

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flenis avatar image flenis Alexandra ♦ commented ·
Tried rebooting first the Cerbo and then the Multis today. No effect. It was a sunny afternoon, batteries around 98%, when I switched on the MPPT after the Multis were back in operation, it was apparent that an initial high effect was produced, close to 2 kW, until the "throttling" kicked in and reduced the solar output to only cover the house load and a trickle to the battery. Double-checked again that DC-coupled PV - Feed in excess is still activated.

I haven't checked the release notes but I guess I could try a firmware update of Multis just to see if it makes a difference?


True, the battery has no communications with the Victron system. There's a BMS for safety and balancing but it's not hooked up for any data at this point. They're NMC chemistry so I've fiddled a bit with the voltages for bulk, float and absorbtion etc. Not quite sure what to experiment with - the Minimum SOC setting, the basic "Keep batteries full" mode or something else?

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Marc Heymans avatar image
Marc Heymans answered ·

You may have to install a BMV so that the cerbo has SOME feedback from the batteries as to the SOC.

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flenis avatar image flenis commented ·
It has the Victron SmartShunt though. It really seems to still balance grid usage to 0W as if feed-in was not activated.
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