Charge current limiting is not working

DIY
, , ,
1

Hi everyone,

Is there anyone here who can explain how to configure the system so that Victron respects the charging limits reported by the BMS?

My setup consists of three MultiPlus 5000/48 units, four MPPT chargers, and Seplos battery storage. The system works great except for one issue: the charge limit.

Victron correctly respects the discharge limit reported by the BMS, but it does not respect the charge limit and continues charging above the value set by the BMS.

Someone suggested that I should disable BMS control and configure DVCC manually. However, when I disable BMS control, the entire system switches to Pass-Through mode and stops charging the batteries. Because of that, I don’t know how to configure the system so that it respects both the charge and discharge limits.

Has anyone experienced something similar or knows what I might be missing?

710538034_35835628489417075_1816660489131238137_n
710538034_35835628489417075_1816660489131238137_n420×288 7.35 KB

710745765_35835731502740107_6051420351527055126_n
710745765_35835731502740107_6051420351527055126_n2286×600 58.6 KB

710059131_35835739629405961_3587232275590254159_n
710059131_35835739629405961_3587232275590254159_n2048×1170 96.9 KB

710079180_35835748029405121_6867639168741665500_n
710079180_35835748029405121_6867639168741665500_n2048×1256 101 KB

2

Are you using ESS? DESS?
Is DC exporting enabled?

There is unfortunately little support on uncertified batteries, so hopefully a configuration issue.

Also, typically SVS isn’t enabled on lithium batteries, it can cause issues.Typically forced off unless the manufacturer wants otherwise.

3

Do you have DC Feedin enabled? Then, no DVCC Charge current limit is send to the MPPTs, they will run full throttle to allow feedin to be possible.

From the manual:

DVCC charge current limits are not applied to DC MPPTs when ESS is enabled with Allow DC MPPT to export. This is to get maximum output from the solar panels for export.

The system however will take care that your battery does not exceed it’s target voltage and switch to feedin, when required.

4

Hi if you mean this limiting i have setting like on the screenshot

image
image2286×780 73.1 KB

I have one more setting that may be affecting why the system is not limiting the charging current.

image
image616×530 21.9 KB

I would really like to understand this, or perhaps there is a manual that explains how the charging limit is determined and which parameters affect it. At the moment, I cannot figure out why the system is not respecting the charging current limit.

5

So, if I understand correctly, when I disable “DC-coupled PV feed-in excess is enabled with ESS”, the system will then respect the DVCC settings and the charging current limits provided by the BMS?

6

There is one more setting that may be important.I have turn on Dynamic ESS

image
image1384×674 61.5 KB

7

I think the BMS Limit is always obeyed. Just the (artificial) Limit in DVCC is not used, when DC-Feedin is active.

The values for DynamicESS are mostly important for scheduling. They will also act as maximums the local dess-delegate is allowing. They have no meaning for regular system behaviour.