Does anyone know of a 12/24 VDC battery bank monitor?

I’m looking for 12/24 VDC battery bank voltage monitors for off-grid wind+solar installations.
I have trawled through various online marketplaces but can’t find one.
Simple once-per-hour measure voltage and uplink over LoraWAN/TTN.
Powered on small battery so deep-sleep cycle required.
Single model with 0V to 30V range would be ideal with accuracy to 1 or 2 decimal places.
Not hard to build with a voltage-divider circuit and regular ADC in many modules.
Preferably +/- screw-terminals to battery bank and SMA to LoRaWAN antenna.
I’m busy and my employer would prefer to buy rather than build.
Does anyone know of one?

There is something from company Victron, they have a battery monitor and now they also have got a Lorawan connector for their internal bus system.
Prob. that´s what you are looking for?

I use some Victron Solar Controllers for a few of my LoRaWAN/TTN GW’s so would be interested in these - do you have a part number/link to hand? (Am just being lazy - will otherwise google for it later tonight! :wink: )

Shoudl be this one:

:+1: Thanks. Think I recall seeing something on this a while back but forgot about it… a bit pricey but may have to get one just to test :wink:

let me know how it works.
I am looking toi build something similar, but I need:
1.) Volt main battery
2.) Volt aux battery
3.) Temperatur inside
4.) GPS position
5.) Plus ev. Volt solar panels (just to see if the sun is out :wink: )

So this does not work for me, I think I will do it with an arduino
MKR 1300 WAN.

What do you think about that idea?

Might be something to lash up on a Things Uno Node or poss take something like a RAK 5205 as start point (GPS + temp/humidity already built in)? (Have used several of these in the past as trackers and local environment sensors). I’ve only played with single battery (of various capacities) on my solar installs but have been thinking of using multiple banks, with graceful failover, as smaller capacities come back up to strength faster and allows any outage recovery to be effected sooner - with the larger capacity coming on later as needed once charged :slight_smile: I havent used the MKR1300 as promised test/eval units never arrived and I didnt think to follow up or source one myself, though no doubt other Forumites have plenty of experience they could share… :wink:

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Thx Jeff for the hint. I will keep that device in mind, but as this are my first steps I think I will stay with the Arduino as I know this one better.

Why!!!

UV sensor is also useful - tells you how cloudy things are

Why not! :wink: If for example monitoring battery in a mobilehome/touring van/Winnabego (sp) or piece of Industrial plant/equipment, road signage etc. then acts as both battery monitor, asset tracker and a GPS/Theft tracker…and whilst a thief might think to remove/defeat a tracker it may not get spotted if its part of the battery monitor/solar charger system :-)… just thinking out loud…

OK, but only as an add-on - embedding GPI (plural) on the side of things just ends up soldering a Taj Mahal on top of the Eiffel Tower.

MKR1300 = SAMD21 attached to a STM32 attached to SX1276 - another WHY? comes to mind.

Hey, yaeh, why not.
The PV panels are already on the roofe of my RV and the voltagebof the PV in combination with the voltage of my battery gives my an idea about the charge state in my RV

Mkr1330 plus GPS shield + temp probe + volt reading (Spannungsteiler, sorry, don‘t knoe the english word).

Should not be that hard

Voltage divider! Google Translate!

Thx - I´ve been on my cellphone and did not think about it :wink:

Knew I had seen before :slight_smile:
Some history:

Also I see Tim (OP) already has experience with this:-

@cultsdotelecomatgmai Tim, what was your impression and experience with the VE.Direct device? Worth trying one? How easy to get data to other dashboards if not using or not focussed on VE’s VRM?

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I have a solar monitor that also measures current flow from panel to charge controller, in & out of the battery and out to the load. Using this, if required / necessary / desired, all sorts of calculations can be made - power usage being the obvious, runtime on battery remaining being the most useful within a margin of error.

But it does not yet have a GPS on it. If I hot-glue one on the side, is this of interest?

The victron MPPT chargers have a well documented serial output that can be parsed and used to transmit. I’ve used this before parsing it to a TTGO ESP32 device at the time to transmit solar voltage,power, current and battery voltage.

I’m currently investigating the option to use the heltec cubecell devices including INA current sensors (ex. INA219) to measure voltage & current via an i2c bus. It would be easy to include a BMP280 or DS18B20 sensor via I2C.

The advantage for my particular usecase (small battery banks charged by solar) is that there is less power consumption while the node is not active (and the i2c devices also powered down) and you receive a bit more data.

edit: should have read the initial post better; see that this post was 2yrs old & you are looking to buy vs build.