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Multiplus 5000/24V Input current limit control assistant in combination with Cerbo

I have a Multiplus 5000/24V in combination with 3 x 24V/160AH LiFePO4 batteries. There are three sources which can be used for charging the batteries, shore power and two generators. One is 18KVA, the other 3.5KVA. When the 3.5KVA is being used the Multiplus has to be limited to use a maximum of 10A.

This system has also a Gerbo GX which is connected to the multiplus via the VE.bus for remote monitoring.

To limit the input current what would be the best solution, use a digital input on the Cerbo GX which will in turn set the input current limit. Or use the "input current limit control" assistant directly on the multiplus?



MultiPlus Quattro Inverter Chargercurrent limit
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Paul B avatar image
Paul B answered ·

both adjustments do the say thing, ie changing the value in the cerbo and changes the value in the multi plus and vicea versa, the only way you can have two different assist settings is to have a quattro unit, as these units have two AC inputs, your only option is to adjust the value manually when using the small gen and then moving back to the shore or large generator.


Another Option MAYBE is to place a battery charger ONLY directly to the small gen say a centura 100 amp unit or skyla and let this directly charge the batteries, The Max that a 3.5Kva gen can run is around 130 to 148 amp battery charger, depending of the efficiency of the charger, this would then remove the requirement to adjust the assist value. but yes you would have to invest in some chargers

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absolute avatar image absolute commented ·

Hi Paul, thank you for your reply.

Your suggestion would work indeed but defeats the whole purpose of having an "intelligent" setup.

The small generator is there for "low power" devices which will be used for longer periods like 230V underwater lights. When the small generator runs it should not or barley charge the batteries and just pass through the 230V.

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Daniël Boekel (Victron Energy Staff) avatar image
Daniël Boekel (Victron Energy Staff) answered ·

Another solution is to use a DMC panel, this has an input that you can wire a contact to to automatically select a different input current limit.

https://www.victronenergy.com/panel-systems-remote-monitoring/digital-multi-control-panel-gx

see 2.2.3:

https://www.victronenergy.com/upload/documents/Manual-Digital-Multi-Control-GX-Panel-EN-NL-FR-DE-ES.pdf

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absolute avatar image absolute commented ·

Thank you for your reply, this seems the only workable solution for now.

I have just installed the Cerbo and connected a relay to the 230V output of the small generator which is connected to digital input 1 of the Cerbo.

This makes toggle digital input 1 to low in case the small generator runs but it seems that you can not set any follow up to this state.

Is there a way to program the Cerbo to limit the current input on AC1 of the Multiplus depending on the state of a digital input?

I assumed that such simple operation would be possible out of the box but I cant find it.


The solution of using an assistant on the Multiplus is also unfavorable as, according to the manual, the Cerbo can't be used to change the maximum input current.

Can you confirm that when an assistant is being used on the Multiplus no external device can change the input current limit?

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