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jazevedo avatar image
jazevedo asked

DVCC, Multiplus and SmartSolar Out of Sync

Hello,

I see a few posts related to the issue but haven't come across any solutions. We have a Multiplus, SmartSolar, Cerbo GX, and Smart Shunt all connected on a yacht (no BMS). The yacht is connected to shoerpower all day/night which keeps the multiplus in a float state. The issue is that the Smart Solar goes into Bulk/Absorption every morning even though the Cerbo GX is setup with DVCC enabled. The Lithium battery bank is nice and happy floating at 13.5V but each morning the SmartSolar, while in bulk/absorption mode, drives the battery bank up to 14.4V. This daily up and down voltage cycle on battery bank is not ideal. Is there a way to ensure the system always keeps the multiplus and smartsolar in sync with charging phase/mode? Just for reference, I have the exact same charging profiles set for both the multiplus and smartsolar.

TIA,
Jonathan

miss-behavin-vrm.png

MultiPlus Quattro Inverter Chargercerbo gxMPPT SmartSolarSmartShuntDVCC
miss-behavin-vrm.png (79.1 KiB)
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2 Answers
Alexandra avatar image
Alexandra answered ·

@jazevedo

The mppts during the day need to bulk produce to send power to loads. This is what is a desired thing yes?

The slight up and down is not bad for lithium's in fact if you read up keeping them at a constant voltage is also very bad for them.

Float from the MP means it is not charging (great since we want to use solar) so that state can be separate since that charger is separate. And in the system. You described us expected when you read the manual on DVCC (each component follows it's own charge algorithm)

If you don't want the up and down in voltage, then set bulk and float to the same voltage.

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klim8skeptic avatar image
klim8skeptic answered ·

@jazevedo Batteries without regular periods spent at the bulk / absrop voltage, the cell balance is likely to drift.

With a full charge cycle each day you could reduce the mppt's absorp time should you be concerned.

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