Monitoring 3 Phase Solar and Usage

Questions
#1

Hi all,
I have a 3 phase house, and we have just added an extra inverter so that the setup is :

2 x SMA 3.0 (no network connections)
1 x Fronius GEN 24 5.0

I want to monitor both solar generation and usage. I realise this is a bit of a messy config (as we bought the house with the SMA inverters already here), but what is the best solution for this monitoring across the three phases and upload to PVOutput?

I’ve previously used an Efergy Engage hub, but this was single phase and fairly easy to setup.

Thanks

#2

Is that four inverters?

So a method I use is 2 x EKM Ominmeter ! v.3. They are three phase inductive measuring meters. The setup is a bit complicated but if you want to get the data.

One EKM meter is setup at the feed entry.

A second EKM is setup with the inductive loops over the the solar feeds.

In my case I have three phase coming in from the grid, and two inverters.

Each of the two inverters is connected to two of the three active phase lines. If there were three inverters then you would use all three loops.

The EKM Meters use a RS485 interface.

The third device require is an EKM push device. This has RS485 input and ethernet interface, and connects the EKM to EKM services, or/and pvoutput by using APIs specific to each meter.

The first EKM Meter for the feed in is set in pvoutput without and calculations applied.

The second EKM using the EKM1-EKM2 calculation to get the correct solar generation.

Example
Example1439×573 71.4 KB

#3

Thanks for the reply lerwick,

No it’s just the 3 inverters.

This is exactly what I want to see from my PVOutput graph. I’m a little unsure of the export of data from the meter to the site though. Does this require a RaspberryPi or similar with use of code? Or is it simpler than that?

To float another idea, could I simply use 2 x Enphase Hub’s with 3 phase clamp systems to achieve the same result? Just thinking through ideas here, and simplifying my setup.

Thanks

#4

Good question about the data upload - you need another device called an EKM Push.

I bought all the bits in 2014 (2 meters with clamps and coils, and the push) for $1,300 direct from EKM. It was a bit of an investment. The EKM Push was a version 2, now they have a version 3. Not sure what the current price is. I bought direct from EKM Metering and it came from US.

So you cable the both EKM Meters using rs485 to the EKM Push. The EKM Push has an ethernet interface. You associate the meters with the EKM Push online (or they come already associated if you buy all the bits at the same time), plug the push into the LAN (or wifi on the EKM Push 3), and then the data is available to pvoutput and a couple of EKM applications - a windows thing called EKM Dash and a web site http://io.ekmpush.com/.

I tried using Watts Clever but found that was problematic. I think the batteries went flat, whereas the EKM is powered from the mains. I had also played around with enphase but that didn’t work out either. EKM seems to be a commercial grade solution.

#5

Thanks for the info :slight_smile: much appreciated!

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