question

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DVCC Limit charge current not working with grid feed in enabled

My System:

ESS with:
3x Multiplus II 48/5000
2x MPPT 250/100
1x Fronius Symo 15 on AC out
8x Pylontech US3000
Cerbo GX

I have a problem with the DVCC feature "limit charge current". I have set the max charge current in DVCC to 60A.
If i enable grid feed-in (AC & DC) the system ignors the max charge current and charges up to the max current of the pylontech battery 296A.
With grid feed-in disabled everything works as expected, the system limits the charge current to 60A.

Is this normal? Am i missing something?



DVCC
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1 Answer
Nico Bayer avatar image
Nico Bayer answered ·

I noticed that the when "limit charge current is enabled", the MPPTs will ignor the max charge current, but the multiplus will stop charging if the max charge current is reached.

So the ve.bus system uses the max charge current, but the MPPTs on ve.can only if feed in is disabled.

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This is a shot in the dark, but probably worth trying as part of the process of elimination. Connect the MPPT’s via ve.direct and see if that makes a difference to the behaviour. Also look at the D.C. voltage readings in the device list on the Cerbo, and see if there is are large differences between the D.C. voltage measured at the MPPT’s, Multi or the Pylontech itself

Same here. Also, the max. charge current set by the BMS is ignored by the MPPTs when operating in the feed-in mode. Saw over 120A when the BMS only requested like 20A. My battery is also a pylontech. The dealer did not seem to care too much and gave me a written statement that this is fine and does not cancel the warranty as stated by pylontech, so I did not pursue this any further...

The regulation is currently broken...