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alexandruy2k avatar image
alexandruy2k asked

BMV-712 with Battery Protect and Smart Solar 75/15

I've asked a similar question before that got answered below and I am using that information
https://community.victronenergy.com/questions/91621/smart-battery-protect-with-smartshunt.html

My current system as I've decided to spend a bit more money is:
BMV-712 + Smart Battery Protect 100amp + Smart Solar 75/15


I have the BMV-712 relay connected to the remote pins on the SBP. With that I am happily controlling the DC loads I have based on the SOC of the battery. This is great as I don't like relying on voltage to keep my batteries healthy because it's a black art to figure out the state of charge of the battery because the voltage depends on what loads I have connected, it depends on if solar is topping up my battery, etc etc.


Anyway onto my actual question can I use the SBP with a relay to connect to the VE Direct RX pin of the SmartSolar so that I can control the SmartSolar load?

I would like to use the smarter features of the SmartSolar to control some loads based on times, but also I would like it that when the BMV-712 decides that the SOC is too low I would like all loads to be disconnected.

Is the alarm pin of the SBP useful at all? Will it indicate if the battery protect is active or not?

Otherwise the other thing I'm thinking is that I could power a relay from the out side of the SBP, and then that relay would connect the SmartSolar RX pin to 0V or 5V.


So can I use the RX pin control function of the SmartSolar in combination with the Streetlight function?

Does anyone know if the RX pin has an internal pulldown to 0V or a pullup to 5V? I'm trying to figure out if my relay would need to connect the RX pin to GND or a 5V source.


Thank you,


Alex


MPPT ControllersBMV Battery MonitorBattery Protect
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1 Answer
kevgermany avatar image
kevgermany answered ·

If wired/configured correctly, the BMV712 takes care of all the guesswork of SOC calcs.

MPPT takes care of battery charging.

So there are two no brainer components in the system that you're trying to replicate, unnecessarily.

Suggest you simply use the battery protect to disconnect the switchable loads based on BMV 712 SOC. Or cheaper, a suitable relay.


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alexandruy2k avatar image alexandruy2k commented ·
I want to take advantage of the extra programmable load features of the smart solar charger, but would also want to override that based on the SOC from the BMV.


So most of my loads are connected to the battery protect and that makes sure I don't over discharge the battery. However I have lights connected to the smart solar charger load output so I can't have them turn on and off based on the time, but I also want to be able to override that in case my solar panels aren't keeping my batteries topped up

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