question

aeneby avatar image

Which device is best to connect the temperature probe to?

I have a setup consisting of (among other things) a MultiPlus inverter, and a BMV-712 battery monitor. Both the inverter and the battery monitor have inputs to accept a temperature sensor, and I'm wondering whether it makes any difference which one I use.


The sensor is currently connected to the inverter, which is fine but if it was connected to the BMV then I could read the temperature in the app. Will the BMV share the battery temperature with the MultiPlus too, so that it can optimize charging?


EDIT: I also have a Venus GX which has temperature inputs too...


Cheers


MultiPlus Quattro Inverter ChargerBMV Battery MonitorTemperature Sensor
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2 Answers
mvader (Victron Energy) avatar image
mvader (Victron Energy) answered ·

Hi, since you have a Venus GX, you could connect a temperature sensor to the BMV. And then let the Venus GX communicate that battery temperature over to the MultiPlus.

See this blogpost that announces that feature (Shared Temperature Sense):
https://www.victronenergy.com/blog/2018/10/17/venus-os-v2-20-scheduled-charging-equalize-and-more/

And make sure to read the DVCC section in the CCGX manual:
https://www.victronenergy.com/live/ccgx:start#dvcc_-_distributed_voltage_and_current_control

WARNING: the temperature sensor for MultiPlusses is not the same one as the one for BMVs. For the BMV you'll need to one that is sold separately as an accessory.


Lastly: I don't know what type of battery bank you have, but if it is 24 or 48 volt, so consists of multiple blocks, then I'd personally be more interested in its balance (so use the mid-voltage monitoring) than its temperature.

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Hi, thanks for the tips. I am running a 24 volt battery bank (2 x 12V), but I already have a battery balancer to monitor midpoints so was thinking that temperature might be good to monitor too. I did not know that the temperature sensor was different for the BMV, I will order the correct one. Thanks again.

Hi I have a BMV 700, and a MultipPlus 24v 3000, and MPPT (24v EasySolar Box).

I don't really want to buy a new BMV702, so hopefully the DVCC shared temperature will support the MultiPlus temperature probe sometime? Then I can simply use that instead. Is it possible to set the shared temperature manually using MQTT / DBUS? I have lots of other sensors around the place I could use! Cheers

mvader (Victron Energy) avatar image
mvader (Victron Energy) answered ·

(This is a bit about the future / software development)


To make shared tempsense work with the Multi temperature; first step was to add it to the dbus; in which there is progress:

https://github.com/victronenergy/venus/issues/374

Expect that in v2.30; Jan Or feb 2019.

And then systemcalc needs modification to support also using the multi temp sense for this; rather than only BMV. Either done also by that time, or otherwise later.


To use any other temperature sensor, @Tim from Eat Sleep Van, you’ll also need to modify the systemcalc python code. To discuss that; please use the Venus developers mailing list.

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Thanks for your reply. Sounds promising. Cheers

Hi mvader,

I just stumbled upon this post and am really happy to hear that work was/is in progress on the option to select & share the Multiplus temperature sensor data. I'm just wondering how it's all progressing & if it's still expected to be released in Jan/Feb 2019?

Keep up the great work!

Regards, Mark.


The beauty of open source development, it's all there to see.

There is no release date attached, just the list of issues, and an engineer assigned to progress them.

Things are getting done though - https://github.com/victronenergy/venus/pulse/monthly


Mark avatar image Mark ♦ Guy Stewart (Victron Community Manager) ♦♦ ·
Thank you for the update Guy.


Yes having the task/issue list and status available for all to see is a very transparent style of development & something I can highly appreciate (I am also a development engineer in the Automotive field).

I will continue to keep an eye out on the progress & its eventual release.

Regards, Mark.