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testor90 avatar image
testor90 asked

Limit the maximal charging current

Dear Team,

I have a very serious problem.

Since expanding my system, the battery charge current is to high.
My batteries can only handle 150Amps, at least this is what i would like them to get.

I did set everything in DVCC, all solarchargers are from Victron and everything is connected.

Still the battery is charged way to fast, tripping my BMS!

What went wrong? Why is this crucial and so importat feature not working?

BMS is NOT connected to my Victron, and i do not want to do this, since this should be an independet layer of safty, im using the Victron shunt additionaly to to monitor my batterys voltages and current.

Thank you!

DVCC
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1234enough avatar image 1234enough commented ·
Unless you are getting payed for exported electricity, disable feed in and MPPT's will throttle once set point for batteries are reached / only re-energize if battery voltage drops.

If you don't get payed for export, all you are doing is supplying electricity for free whilst wearing out your equipment.

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nickdb avatar image
nickdb answered ·

Are you feeding back? If you set "limit max charge current" in DVCC and all your chargers are physically wired to the GX, it should not go beyond this.

Only exception is if feed-in is enabled, then this parameter is ignored.

Then you will need to set the individual limits on the inverter and MPPT's via veconfigure and Victron connect.

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testor90 avatar image testor90 commented ·
Thank you for the answer,


Yes i am feeding back power, I even want that the power that is "to much" for my batteries to be feed in.

This is exactly what I am looking for.

Batteries are charged with 100A and everything above is going into the grid.

In the summertime I will set it even lower 70A, since I have more time to charge up and it will make my batteries last longer.

How do i configure this? Its the most important feature for me.

Sincerely
Adam J


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nickdb avatar image nickdb ♦♦ testor90 commented ·

Hey Adam, this is a bit of a common problem, particularly when using batteries off the certified list, or unmanaged ones.

You have two conflicting settings: Feed-in and battery charge limits in DVCC.

As mentioned feed-in ignores the limit you set, this is documented in the DVCC guide, and is to allow the MPPT's to run unrestricted for feeding back.

There isn't a simple answer, you can manually set charge limits on the MPPTs, this will also restrict what you can feed back.

You may have to do some bedtime reading.

On the modifications section, some users have got creative with nodered and scripting to try wangle their way around the problem. You may need to go do some digging/searching there as there are a number of posts on this subject.

You could also consider changing the charge voltages on the MPPTs but this will only help near higher states of charge.,


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testor90 avatar image testor90 nickdb ♦♦ commented ·
Thank you,


Well i hope this is not seriusly the case, every other system supports this feature.
And it would be very important, and also getting even more important with restrictions to feedin.

I will write to Victron directly, this must be possible, have i known this in advanced i would have chosen an other system.

For what did i pay so much money if the such a basic feature is missing?
Even Deye offers this for a fraction.

Thank you.
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kevgermany avatar image kevgermany ♦♦ testor90 commented ·
Victron does have this function. But the batteries must talk to the GX device and be on the supported list.
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testor90 avatar image testor90 kevgermany ♦♦ commented ·
​I have the 280k cells with BMS from Daly.


Mby if i change the BMS?

Would this help?

Thank you !


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derrick thomas avatar image derrick thomas testor90 commented ·
Daly can be integrated to communicate with victron gx device. See here

https://github.com/Louisvdw/dbus-serialbattery

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marekp avatar image
marekp answered ·

@TestOr90

You have couple options.

1. Add more batteries,

2. Limit charge current on you MPPT chargers,

3. Replace some of your MPPTs with ON-grid inverter.

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testor90 avatar image testor90 commented ·
Thank you but those options are not good.


1) More batteries are not needed, and would be a waste of money.

2) if i limit the charge current on mppts i will not have exported energy. making my bigger system not worth the money.

3) this would be possible. but bad because in the winter i want everything to go into the battery and the ac/ac coupling is not efficient. (also i already bought victron mppts)

But thank you for the input.


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Related Resources

DVCC chapter in GX manual