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Energy monitor with NO Wi-Fi

Spruce Goose

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Joined
Mar 14, 2023
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6
Location
Maine
Hi all.

First post here. Looks like a good resource.

I manage a couple off grid cabins that run some loads off a small (2, 280 watt panel) solar system with 24v, 400Ah lead-acid battery storage. These cabins get rented, and it's tough to know how much energy is being used. We're looking to upgrade the solar array capacity.

I am looking to get an energy monitor, but everything I find needs wi-fi. Any leads on a device that will log the data internally? It would we good if several weeks to a months worth of data could be stored and then viewed or exported for computer viewing.

I came across loggers like ones shown here: https://microdaq.com/data-loggers/energy-power.php
but I don't think these are really energy monitors so much as voltage / current quality trackers (not nearly enough sampling it seems).

Our system uses a Conext SW inverter, which does appear to have ability to connect to a 'Combox.' It sort of looks like this Combox might log energy usage?
 
If you can figure out the data format from the context inverter, you could use a Arduino to record the data to an SD card.
 
Hi all.

First post here. Looks like a good resource.

I manage a couple off grid cabins that run some loads off a small (2, 280 watt panel) solar system with 24v, 400Ah lead-acid battery storage. These cabins get rented, and it's tough to know how much energy is being used. We're looking to upgrade the solar array capacity.

I am looking to get an energy monitor, but everything I find needs wi-fi. Any leads on a device that will log the data internally? It would we good if several weeks to a months worth of data could be stored and then viewed or exported for computer viewing.

I came across loggers like ones shown here: https://microdaq.com/data-loggers/energy-power.php
but I don't think these are really energy monitors so much as voltage / current quality trackers (not nearly enough sampling it seems).

Our system uses a Conext SW inverter, which does appear to have ability to connect to a 'Combox.' It sort of looks like this Combox might log energy usage?
It does. I have been using a Combox in an Schneider SW system for almost 7 years - and it stores that data with varying degrees of detail to a usb stick. Also Very Handy for monitoring and making system changes from an ipad, computer or iphone.
Screen Shot 2023-03-14 at 12.25.28 PM.png
 
If you can figure out the data format from the context inverter, you could use a Arduino to record the data to an SD card.
I assume this would entail a good deal of friggin around? Like would it entail soldering components together and/or programing. Both are likely off the table for me. Do you have any links to descriptions of this process?
 
I came across loggers like ones shown here: https://microdaq.com/data-loggers/energy-power.php
but I don't think these are really energy monitors so much as voltage / current quality trackers (not nearly enough sampling it seems).
I bought a couple of these "Data View Current & Voltage Data Logger" They are powered by internal batteries that last 6 mons? kind of thing - it can very depending on frequency of sampling. They have some software to see / extract data over a USB connection to the units but it was an *old style* windows app. And I couldn't automate the software to do data extracts even thru a based test script to drive the GUI. It wouldn't reliably connect to multiple units (with different IDs) thru the automation - I had to fool with USB plug/unplug kind of thing.

They worked but are expensive and I needed remote / automatic data extraction. Here's an example where I caught my 1997 AC compressor going crazy amps on startup to show the kind of data logging it can do - set to 5sec intervals here.
This is: entry ID, amps, volts, date/time.
1679325187168.png
Notice the 95.4amp @ 196.4v!! Have since replace this old AC unit with a modern heat-pump :)


I know what you mean by no Wi-Fi (and I avoid bluetooth/phone like the plague) - but honestly you could setup a small, local, closed network with wifi router and an Iotawatt could be made to work. You'd need a WiFi router and a computer (Rasberry Pi would work) with a time service running. There is an Iotawatt community forum you might get specific info - https://community.iotawatt.com/ The Iotawatt has built-in graph and query API so you don't need any external apps to see/access data. Here's an example graph of my inverter #2 output over a day
1679324904341.png
but you can get quite sophisticated graphs by uploading to InfluxDB (which can be local or cloud) as an example.

Not pushing Iotawatt - just been a little bit where you are and a small local network w/WiFi is not the worst thing in the world.
 
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Will happy sit logging in the absence of WiFi
Logging to what? How would I get that data?

OffGridInTheCity's reply makes it sound like I would have to set-up a network.
I appreciate the thoughts! I am ideally trying to keep this as simple as possible. It's for work, and this I cannot afford to spend a bunch of time fussing around with something. A little fussing is ok. Alot... not so much. :)

I have eyed Iotawatt for home use (where I have wi-fi). I currently have a Lantern Power Monitor, which uses a raspberry pi. All uploaded to servers though.
 
Here's an example where I caught my 1997 AC compressor going crazy amps on startup to show the kind of data logging it can do
I suppose there would be some mathematical way to gather approximate (trendline) energy usage using that data... so long as it can store enough data points for several weeks. hmm. Trying to think how I could get energy data from that easily. Maybe just an excel sheet with a multiply formula (voltage x current x 5 seconds=watt-seconds ?) Assumed power factor of 1.
 
Logging to what? How would I get that data?

OffGridInTheCity's reply makes it sound like I would have to set-up a network.
I appreciate the thoughts! I am ideally trying to keep this as simple as possible. It's for work, and this I cannot afford to spend a bunch of time fussing around with something. A little fussing is ok. Alot... not so much. :)

I have eyed Iotawatt for home use (where I have wi-fi). I currently have a Lantern Power Monitor, which uses a raspberry pi. All uploaded to servers though.
Iotawatt is a small computer and logs the data to it's local disk current and history logs shown in pic below. The local graphing reads local data. I'm currently monitoring the power coming out of each 120v leg of my 240v/120v inverter #2. I'll be expanding this to inverter #1 and generator incoming power as well.
1679346934021.png

The simplest form of local data 'extraction' is via the built-in API Query - https://docs.iotawatt.com/en/master/query.html

Here's an example query to get csv formatted output - http://iotawatt.local/query?select= [time.local,I2Black.Watts,I2Red.Watts]&begin=2023-03-20T14:00:00&end=s&group=5s&group=5s&missing=0&format=csv
2023-03-20T14:00:00, 398.2, 812.9
2023-03-20T14:00:05, 383.7, 835.9
2023-03-20T14:00:10, 386.1, 811
2023-03-20T14:00:15, 384.4, 765.4
2023-03-20T14:00:20, 386, 770.6
2023-03-20T14:00:25, 380.2, 818.8
2023-03-20T14:00:30, 386.5, 813.5
2023-03-20T14:00:35, 385.6, 762.7
2023-03-20T14:00:40, 382.8, 800.4
.....

My use/example is really basic compared to what it can do overall. Suggest reading thru some posts at https://community.iotawatt.com/latest and you'll get a better overall view of what it can do.
 
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It's internal SD card, and via your phone/tablet via it's AP
It's an internal SD card. You access it by browser.
*Its an open project, you can change SD cards if one wears out or get's corrupted and presumably read the old one. I'm not going that route but I think the IotaWatt forum will quickly answer any specific questions you might have.
 
It's an internal SD card. You access it by browser.
*Its an open project, you can change SD cards if one wears out or get's corrupted and presumably read the old one. I'm not going that route but I think the IotaWatt forum will quickly answer any specific questions you might have.
I own numerous, it wasn't me asking questions.
 
So this is an income property? Best to treat it that way that then.

I have more than a few remote assets that I monitor remotely with this. Very pleased overall. Just my 2 cent's.
 
Hi all.

First post here. Looks like a good resource.

I manage a couple off grid cabins that run some loads off a small (2, 280 watt panel) solar system with 24v, 400Ah lead-acid battery storage. These cabins get rented, and it's tough to know how much energy is being used. We're looking to upgrade the solar array capacity.

I am looking to get an energy monitor, but everything I find needs wi-fi. Any leads on a device that will log the data internally? It would we good if several weeks to a months worth of data could be stored and then viewed or exported for computer viewing.

I came across loggers like ones shown here: https://microdaq.com/data-loggers/energy-power.php
but I don't think these are really energy monitors so much as voltage / current quality trackers (not nearly enough sampling it seems).

Our system uses a Conext SW inverter, which does appear to have ability to connect to a 'Combox.' It sort of looks like this Combox might log energy usage?
Have you looked at https://efergy.com/emax-kit/?v=06fa567b72d7?

Non wifi enabled although the display unit is wireless. You can plug in a USB to download readings. You can even set tarrifs see peak demand etc.
 
Have you looked at the "EmonLib.h" library for Arduino? Details can be found at: https://openenergymonitor.org/
I have set up such a system within my solar project. All data is saved on a microSD card. I save a month at a time, but probably could record more. My guess is that you'd be limited by the file size that your program can handle.
 

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