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Victron Direct

HaldorEE

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OK, it has been hours since I stirred the pot.

I was looking at another thread and once again was wishing that the BMV-712 had an extra relay output. Got me to thinking. The BMV-712 communicates using Victron.Direct and the communication protocol for Victron.Direct is pretty simple.


How about a dongle that plugs into a BMV-712 and provides multiple status outputs as relay contact closures.

I haven't looked into the configuration of the BMV-712 yet, but I was thinking it would be neat to be able to have a number of different outputs. I realize this could be done using a CerboGX, but bear with me here.

Outputs:
  • High battery SOC or low temperature disconnect to turn off your charge sources (like an Orion-TR DC-DC charger, a Multiplus)
  • Low battery SOC or high battery temperature disconnect to turn off your loads (like dumb DC loads or a Multiplus or a non-Victron Inverter that has a switch input)
  • Low battery SOC Alarm to let you know that your battery is getting low (so you can turn off the AC before the lights go out).
  • Long Term Storage Output. Use this to switch an outlet off once the battery has discharged to say 50% SOC. This way you can easily get your battery to the appropriate SOC for long term storage.
I know everybody immediately thinks of using a fancy Linux based board with a display like a Raspberry Pi, but that is serious overkill for this application.

I am thinking about something like this combined with a relay or optocoupler PCB. $5 and the size of your thumbnail.


Use something like this to drive relays.

 
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I like this idea. maybe an arduino would work as the victron.direct interface between the BMV-712 and the output relay board ? I will confess I don't know much about victron.direct so will have to read up on it. I am currently using the BMV-712 relay for controlling my battery heaters thru a single SSR. would love it if other outputs were available.

<sorry> didn't recognize the digikey part you listed; but it is an arduino.
 
My preference is for NXPs line of LPC processors (last one I used in a design is the M33 dual core LPC55S69), but I like pretty much any ARM Cortex M processor.

I am halfway considering using a Nordic Semi nRF52 module so I can use BlueTooth to talk to the BMV-712. I have used several different Nordic Semi modules in different wireless load cell projects. I used an nRF52832 and an nRF52840 in my last project (same project that used the LPC55S69).

My designs used surface mount modules. This one is through hole so it will be much easier to experiment with.

 
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I like this idea. maybe an arduino would work as the victron.direct interface between the BMV-712 and the output relay board ? I will confess I don't know much about victron.direct so will have to read up on it. I am currently using the BMV-712 relay for controlling my battery heaters thru a single SSR. would love it if other outputs were available.

<sorry> didn't recognize the digikey part you listed; but it is an arduino.
Me too. I have a BMV-712, but it is still in the box waiting for me to get to the point where I can install it. Once I get to that point, I will dive into configuring/using it. Right now it has still got that halo of "hasn't disappointed me yet" around it.
 
Downloaded Victron Direct Protocols. There are two, a human readable version and one that is hex formatted.
 

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  • VE.Direct-Protocol-3.29.pdf
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  • BMV-7xx-HEX-Protocol-public.pdf
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