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gnagflow avatar image
gnagflow asked

dvcc max charge voltage not working - why

Hello, I tried to use the DVCC max. charge voltage several times at different ess systems, but it never worked. I need to reduce the charge voltage in ess only during summer, when the batteries are always full, customers asking those settings, because they want to increase the life of the batteries, full charge is always bad, in summer batteries stay long time at full charge, see picture.

I tried to update to GX 2.90 but doesnt work.

I tried it at systems with CAN bus controlled battery (REC-BMS for Victron) and at systems without CAN controlled battery.

Always, the Multiplus2 is charging the battery until either the BMS switches the CCL to zero or without CAN bus battery the multiplus charges until it arrives its max. voltage set by ve-configure.

It never accepts the DVCC max. charge voltage, WHY? Why does this important feature do not work for any of my customer installations?

Thank you for your help!

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ESSDVCC
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3 Answers
nickdb avatar image
nickdb answered ·

Have you tried it without the shared voltage sensor enabled in DVCC?

Generally with lithium batteries and higher voltages it would be disabled.

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gnagflow avatar image gnagflow commented ·

Thank you for you input, but unfortunately the change has no influence. DVCC max. voltage has no effect, see picture from right now:

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nickdb avatar image
nickdb answered ·

No idea why it doesn't work for you. Is this a CAN BMS and the mppt's are all reporting BMS external control?

If I set a lower voltage maximum, the system takes a few seconds then starts discharging the battery until the voltage is reached. So working perfectly.

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nickdb avatar image nickdb ♦♦ commented ·
This setting wasn't intended for this use case, it was primarily designed to help with battery balancing. It also will only work with a managed battery, it does not work with lead acid/unmanaged batteries.
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gnagflow avatar image gnagflow nickdb ♦♦ commented ·

Hi Nick,

i have different use cases with lithium batteries where it doesnt work for me. a) cases where the battery manages via canbus the multiplus via sending CVL, CCL and DCL values. b) lithium batteries with bms which is not connected to victron gx, where max. voltage for charging is depend on ve-configure settings of the multiplus. why shouldnt the dvcc voltage work, all other parameters of the dvcc such aus max. charge current, shared values do also work in all systems. Its a pitty, because I asked for a max. SOC feature, but there is an max. Voltage feature that i cannot use.

Do you have a hint why it is not working?

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gnagflow avatar image gnagflow gnagflow commented ·
i mean in my case i have also managed battery systems, where the dvcc doesnt work (batteries with REC BMS)
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nickdb avatar image nickdb ♦♦ gnagflow commented ·
The challenge is REC is unsupported and this feature works with supported batteries. I will move this to modifications space for you. Maybe you will get a better answer.
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baxter avatar image baxter nickdb ♦♦ commented ·

Limiting charge voltage works completly fine with REC-BMS (use it since month).


@gnagflow The REC-BMS is dedected in the Device list? You configured it as battery monitor? Which CVL does the BMS send to DVCC? Just to be sure, ESS is installed and configured?

As I already tolt, using voltage to limit the SoC Is just a bad idea, but in this community it is like feeling of banging the head against a wall

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johanndo answered ·

Read the manual of the cerbo, the section about DVCC, what controllers and BMS are supported and what not and how DVCC acts or doesn't act on unsupported devices. REC delivers the Victron parameters and acts like a Victron BMS, fully supports DVCC, but with a Victron specific firmware only, you have to ask for it when ordering, you can install it later too - the hardware is the same. You have to configure the parameters ON THE REC ABMS to take effect, they are changing dynamically to control charging. The parameters on the Cerbo are the upper bonds only.

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