question

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busta999 asked

Multiplus II 5000va/Cerbo and 20kWh batteries, want to add solar for test

Could use your solar expertise.



I am looking to add 2 x 435-NEG9R.28 TRINA 435W TYPE N VERTEX S PLUS BLK & WHIT BACK solar panels
to the Victron multiplus II 5000vA with a Cerbo and 20kWh of batteries running at ~52V.
This is just is a test so I can work out expected generation and how I will manage it against car/house batteries.

I am trying to work out which MPPT to get I am looking at

Victron Energy SmartSolar MPPT Solar Charge Controller (Bluetooth) - MPPT Charge Controller for Solar Panels - 100V 20 amp 12/24/48-Volt

I know I will have to replace it later when I add on a lot more panels, but I can’t add them on until we replace the roof on the outside buildings which is a couple of years away.

Any ideas, thoughts or recommendations?

Also any pointers to setting up Multiplus II would be appreciated.



Multiplus-IISolar Panel
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2 Answers
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busta999 answered ·

Ok looking at the Victron MPPT sizing Calculator it does suggest for

the two Trina solar energy 435W-44v TSM-435NEG9R.28


I can use a Victron MPPT 150:35

It States the PV power ratio is 44% (undersized) in fact every MPPT option is undersized ranging from 15% to 44%.

I am not planning on adding other panels for a couple of years and will be adding another 8-10 so will need another MPPT for those.


Any advice, thoughts or suggestions?

This is just a test run for 2 years to work out what we could get of the panels here and how I manage them with the batteries/overnight off-peak and EV using home automation.



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busta999 answered ·

Ok it all looks good, no space for expansion but that is not an issue.

Got the SmartSolar MPPT 150:35

VE Direct cable to go from MPPT into Cerbo

2x Trina 435W Vertex Plus NEG9R.28

20m of 4mm core cable

Panel mounts for flat room

and all the connectors.

Once in will wire solar into MPPT - MPPT into Lynx

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Related Resources

Additional resources still need to be added for this topic

MultiPlus-II Product page 

MultiPlus-II Manual

Multiplus-II GX Online Manual

MultiPlus-II 230V Datasheet 

VE.Bus Error codes