question

thomash1302 avatar image
thomash1302 asked

Using a Multiplus to automatically cycle batteries for testing purposes

Hello all,

For an engineering project, we want to cycle lead-carbon 12v batteries to test their effective degradation. This grid-connected system should constantly charge and discharge batteries according to a set voltage or SoC. We have 2xMultiplus 12/500 in parallel and a cerbo gx to monitor the system. Is there a way to program the multiplus inverters to do this behaviour (with assistants or relays) or should I add a PLC and put the system in modbus slave mode?

The batteries will be tested each week in our controlled battery tester to check for degradation.

multiplus ve.busmultiplus in paralleless settings
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
derrick thomas avatar image
derrick thomas answered ·

Use conditional AC input.

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

kevgermany avatar image kevgermany ♦♦ commented ·
@Thomash1302 also use smart shunts or BMVs to work out SOC.
1 Like 1 ·
thomash1302 avatar image
thomash1302 answered ·

Thanks for the suggestions. I am now programming something in the node red extensions of the Cerbo


2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

valentin-silvera avatar image
valentin-silvera answered ·

Hello @Thomash1302 , I have the same challenge as you. Let's use the node rede for this.
We already have experience using node red in other applications withc Victron.

Now we are trying to know how we can configure the DC power requested for the battery because the victron modbus registers seem like it is only possible to configure the AC power injected into the grid so we would have to do a control loop to adjust the power injected into the grid as a function of the power required on the battery.

Have you made any progress on this matter?

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

janieronen avatar image janieronen commented ·
Pretty old conversation but I have managed to cycle test batteries with using DVCC DC current limits. So adjusting limit to amp what like to charge or discharge and then requesting more power than that.



Using also same method for controlling special batteries by setting SOC based conditions in nodeRED to limit charge current to wanted level example over 95% SOC.
0 Likes 0 ·