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hessi9 avatar image
hessi9 asked

4 times higher idle consumption of parallel connected Multiplus II

I use 2 Multiplus II 3000 at an island system. When running each single Multiplus II at default settings the idle consumption is close to the 11w of the spec. After I connected them in parallel and configured the master as Self-consumption Hub without feedback the idle consumption increased to unacceptable 90w total.

I guess connecting the Multiplus in sequence could solve this problem - the fist Multiplus acts as input for the second Multiplus.
The second Multiplus would run best with some kind of load balancing config like
- limit input current or inverter to 5A if load <10A
- limit input current or inverter to 10A if load <20A
...
How can this be done?
Does this design have disadvantages I don't see?

multiplus in parallelisland mode
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2 Answers
Michelle Konzack avatar image
Michelle Konzack answered ·

I think, there is something wrong with your cabling and the two MultiPlus-II 3kWA try to balance between each other.


I have (currently) two MultiPlus-II 24/5000 and my power consumption is around 470Wh a day for my first (regular) MultiPlus and around 510Wh for the secondary (loaned) one.


The cable from the battery power rail is 2x 70mm2 (continius load 686A and 1600A max) for PLUS and MINUS with around 1,5m lenght to the NH-Lasttrenner.


The DC cables from the NH-Lasttrenner (3x250A) have 70mm2 and are STRICKT the same lenght of 130cm within a tolerance of +-0,5cm.


The AC cables from the MultiPlus to the joiner (I can have up to 3 MultiPlus in parallel) have around 80cm with 4mm2 and a tolerance of +-1cm.


Have you verified the correct cabling in your system?

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Duivert NL avatar image
Duivert NL answered ·

Yes is definitly a cabling issue, have you followed the instructions in this manual? And in wiring unlimited?

https://www.victronenergy.com/live/ve.bus:manual_parallel_and_three_phase_systems

https://www.victronenergy.com/upload/documents/The_Wiring_Unlimited_book/43562-Wiring_Unlimited-pdf-en.pdf

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