Measuring the loads of the house

tccack

New member
Joined
Dec 17, 2018
Messages
26
Hi all... First post after lurking for a long time. Hopefully its posted in the right spot.

I have a house which is wired up three phase.
Currently I have a 9.88kw solar system on it with an SMA tripower 10KW inverter.

In order to plan for a battery system I would like to first connect a data logger on the main supply to see what my grid in vs grid out vs consumed solar is and the total, peaks and average power consumption numbers are.

I've previously monitored the house but this excluded many things in the shed such as freezers, lights and welding equipment and it wasnt a logging device just a cheap, "keep an eye on it" type thing.

Does anyone have a suggestion for such a device (used is very much OK) that can be attached in there somewhere and log the data to a memory card?
I'm wondering if I need a 6 clamp device? 3 clamps for measuring solar power used and exported and 3 clamps for grid used as the output on grid wires will be measured on the solar exported clamps.

Hopefully this makes sense?

Cheers

Tony
 
http://www.iotawatt.com


image_vlnmgo.jpg
 
Sean said:

That looks like exactly what I am looking for... I'll investigate this one!!!

It seems like rather than use CT's for devices on the Dist Board I can just use them on the phase wires as there are so many inputs available.


Cheers!
 
The numerous inputs allows for per circuit logging if required.
 
If you're not afraid to build a meter, you can also use the OpenEnergyProject device. I've built this and works really well
 
iotawatt is also open source and can be built. I have such a project to but more towards static units like the SDM.
 
Took a look at the open energy project device.

I think building the meter would be quite interesting. I have some questions though about how to do this with 3 phase grid tied inverter though.
I do need to measure each phase as the house has a concentration of lights on one phase and power outlets on another. There is also quite a few three phase devices that are used such as A/C and welding equipment.

I'll have to head over to the energy project forum and post some questions perhaps to see if its been done before.

I have no issue however with buying out of the box if it does the job so the iotawatt seems like it could do the job (pity they dont have australian powerplugs for voltage reference though)
 
SDM630 can do 3phase but its intrusive. I use several of them. Yeap cost some bucks but its well worth it if you want 100% controll. You get all in 1 device that do everything. It even holds memory. Add ESP or Rasp or other device that do Modbus and your set.
 
If you go through Open Energy site, they show a diagram where they are reading 3-phase. I don't recall where at though, it's been awhile since I've read through it. Their forum is really active as well and the project managers/designers will respond fairly quickly.
 
Unfortunately the iotawatt doesnt seem to actually do three phase unless you open the box and remove some components. They are working on a true plug in three phase unit (with proper jacks for 3 voltage references) due out middle 2019.
SDM630 does look like a very simple thing to install to the board ( I have the space on the rails etc ) but would I need 1 or 2 of them.
Not sure about the modbus addons... thats foreign territory to me.

I want to get data on what the solar is making versus exporting and what is being imported for consumption.
I could start with 1 as my first priority is what the consumption is regardless of source.
I want peaks, averages etc logged over a significant time to learn what battery requirements are for the future.
 
You need 1 per plase you meassure. It measures both ways... I got 4 of em. So i meassure 12 phases total. You could say...
 
As you all know I value you opinions on this board a lot and I have been following this thread with great interest.
I am getting ready to pull the trigger either ontheIoTaWatt, or the emon.I am leaning toward the IoTaWatt
The IoTaWatt with its 14 inputs seems like the logical choice. If I understand correctly you just need a Raspberrypi unit if you want to do graphing etc.
The emon has a sensor node and a base station that basically do the same thing except it has less inputs.I assume that additional sensor nodes can be installed and added to the base station.

One question I do have is extending the CT cabling on either unit. I again assume a properly shielded 3.5mm jack male/female extension cable should work.
Max distance would be 15 feet.

Update: Found the answer need to make the cable.https://learn.openenergymonitor.org/electricity-monitoring/ct-sensors/extending-ct-cable

Additionally the IoTaWatt is veryreasonably priced and in the US.

Your thoughts?

Wolf
 
CT cables can be extended over 50m if you pay attention to routing and maintaining twisted pairs.

PV Output online logging support is inbuilt, as if Grafana, you just need an account (Iottawat) - or use the EmonCMS for visualization (they've just started a per feed change scheme)

And dont forget theres an instance of EmonCMS running on the Iottawat, so local network graphing is built in.
 
Sean said:
CT cables can be extended over 50m if you pay attention to routing and maintaining twisted pairs.

PV Output online logging support is inbuilt, as if Grafana, you just need an account (Iottawat) - or use the EmonCMS for visualization (they've just started a per feed change scheme)

50m, nice. This makes remote sensing a little easier.

Creating an account on an internet based site just so you can get your local readings. This is one thing that puts me off from going with those types of services. There's no reason why you can't have it local. It doesn't take much resources at all to do this. Just another gimmick to get peoples money. This is one reason why I went the Emon path and built my own from the instructions. Is it perfect, no. But I learned a lot from it. Also gives me a chance to learn other details. Not that this is a method for everyone, I agree.

Maybe the Iottawatt can be configured to dump to a local server, I don't know. Haven't looked into it that much.
 
Korishan said:
Creating an account on an internet based site just so you can get your local readings.

Haven't looked into it that much.

Clearly you haven't looked into it much - all readings are available locally, and there's no need for an online account, unless you want to view data away from your local network, or combine it with an existing PVoutput for integration with previous PV logging.

Some attention has to be paid to cable length, but CTs aren't known for their across the range accuracy anyway.

https://www.schneider-electric.co.uk/en/faqs/FA221505/
 
Sean said:
CT cables can be extended over 50m if you pay attention to routing and maintaining twisted pairs.

PV Output online logging support is inbuilt, as if Grafana, you just need an account (Iottawat) - or use the EmonCMS for visualization (they've just started a per feed change scheme)

And dont forget theres an instance of EmonCMS running on the Iottawat, so local network graphing is built in.

OK I like it!

So far the IoTaWattis the choice.


Wolf
 
Sean said:
Korishan said:
Creating an account on an internet based site just so you can get your local readings.

Haven't looked into it that much.

Clearly you haven't looked into it much ....

Just going off what you said earlier. And I believe I did say that I didn't look to far into it. And it's because I chose not to go with them.

I didn't go with Iottawatt partly because of cost. Just because it's affordable for some doesn't mean it is for everyone.

Wolf said:
So far the IoTaWattis the choice.

Keep us updated on your progress. :)
 
Korishan said:
[quote pid='43871' dateline='1547741887']
So far the IoTaWattis the choice.

Keep us updated on your progress. :)
[/quote]

Will do. :)


Wolf


Sean said:
The developer (Bob) usually answers questions very fully, and within just a few hours if you need info from the horses mouth.

https://community.iotawatt.com

Well I tried to sign up for the community but haven't gotten my activation email yet so I'll ask this question here.
Maybe you guys will know.

I already have 2 CTs 1on my L1 and 1 on myL2 for my GTIL2 which is working just fine.
By adding another set close to the CTs (probably right next to each other) would there be any interference between the 2?
I am thinking not as the coils are encapsulated in their own ferrite field but the question remains.


Wolf
 
Back
Top