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rickp avatar image
rickp asked

Multiplus AC Ignore, can a BMV712 send SOC?

I have a Multiplus 24/3000/120 that I want to prioritize solar charging from a SS-250/100. Grid power is available, and is to be used as a backup for solar issues.

I am using BattleBorn 12V LiFeP04 batteries in a 2S2P configuration.

I have found the voltage setting option for AC Ignore to be unusable with LiFeP04 batteries because voltage doesn’t fall as precipitously with SOC as it does for lead-acid or AGM chemistries. For example, at <30% SOC, voltage is still at or slightly above 26VDC.

I have a BMV712 monitor on the system, and wondered if it can be paired with the Multiplus to provide SOC data. Any info, along with required cabling, would be most useful.

Otherwise, it appears my only option is a rather expensive addition of a Color Control GX or Venus GX.

Thanks in advance!

MultiPlus Quattro Inverter ChargerBMV Battery MonitorLithium BatteryAssistants
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rickp avatar image rickp commented ·

After consulting with my vendor, BattleBorn Batteries, I am working on another setting, still in the virtual switch section, but voltage based only. If it works as desired, I will update here.

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rickp avatar image rickp rickp commented ·

The AC Ignore function works based on the new settings. While not as simple as using a percent state of charge number, which requires several hundred dollars in additional equipment for my system to provide that data to the Multiplus, you can use voltages once you know what a commensurate VDC to SOC number is. I set mine to 26.1 VDC, which approximates a 30% SOC as a relay closing point (grid AC connected), which allows the system to charge the batteries. Then I set it to go back into AC Ignore status 15 minutes after bulk charging was complete. This worked well for my intention, and will allow solar to carry the load unless conditions don't provide enough power.

I am going to fine tune it while in use, as I don’t want it charging to full capacity on grid power just before the sun comes up and creating a time loop that defeats the purpose. There are a variety of settings I can use within the application, so I’m sure I’ll fine a suitable group of settings. But at least I know I am on the right track.

I hope this information is useful to others attempting the same “solar prioritizing” with similar Victron equipment.

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green-monster avatar image green-monster rickp commented ·

Thanks, do you have to manually monitor bulk charging to select AC ignore? or is it in your settings so it is automated?

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rickp avatar image rickp green-monster commented ·

It is in the settings of the Multiplus. I eventually settled on using a virtual switch based on voltage, which has been close enough to get what I wanted. I used voltages that approximate a certain SOC as on and off settings, which has worked well.

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Simon Schneider avatar image Simon Schneider rickp commented ·
Hi, how much delay did you put in to switch back to AC since if you have a big draw, or draws in general, the soc is way lower then what the actual SoC is at this moment.
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1 Answer
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Paul B answered ·

have a look at setting up assistants being hub4 or ess assistants as these can help out with power exporting options and also include SOC battery settings, Presuming you have a victron Venus device in the system that is

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