Australian use

I am from Australia and this product interests me. Firstly I want to monitor Solar production, Solar usage, Solar exported to grid, Grid usage in real time. I have 3 phase power. Which product is best for what I am after. Also any other accessories that I may need for it to be able to run in Australia. Thank you

We have many users in Australia. For three-phase installations, there are basically two approaches:

  1. Use an emonTx across all three phases. Because this has only one voltage input, the measurements are an approximation - how good or how bad depends one how well balanced your voltages are, and how stable your mains frequency is. You can measure 4 currents (3 phases plus one other) with an emonTx.
  2. Use an emonTx per phase, treating each phase like a single-phase UK installation that the emonTx was designed for. That way, you need a minimum of 3 emonTx’s, but you get to monitor 4 currents with each.

Looking at your requirements, exactly which currents you measure depends on where you can install current transformers, and where your PV infeed is in relation to everything else. With the emonTx, you can know the direction of power flow, so monitoring the grid feed upstream of any branching circuits, you know the nett grid power. You can separate import and export in the software. If you can access the PV infeed, you can measure that too (or you may be able to have a pulse input from your generation meter). Doing the maths on those two values will give you nett consumption.

If you have one emonTx and a pulse feed from your generation meter, all you need is that plus an emonBase (Raspberry Pi with a radio receiver to listen to the emonTx) to collect and display the data, or sent it on to or wherever.
If you haven’t got the pulse input to measure generation, then you’re looking at a second emonTx to do that.
If you feel you need the accuracy that an emonTx per phase will give you, plus the option of measuring some more individual circuits, then three emonTx’s are needed.
Each emonTx will need an a.c. adapter and c.t’s as necessary. Your emonBase will need a case, a 5 V USB supply and access to your LAN via Wi-fi or Ethernet.
If you want to run our 3-phase sketch, you’ll need a programmer to load, configure and calibrate it.

You want to measure in “real time”. The standard sketches report every 10 s - this is the maximum rate that will accept. If you have emoncms on your Raspberry Pi (or a NAS or another server somewhere) then that limit doesn’t apply and you can alter the sketch(es) to report as often as you wish - bearing in mind it can create a lot of data. If you’re reading pulses, by their very nature you know nothing between pulses, so you might wish to consider that when deciding between pulses and c.t’s and another emonTx.

An emonPi is unlikely to be attractive to you, having only two current inputs.

Thanks for the info Robert,
I am not a very tech savy person. With what you have detailed exactly
what do I need to purchase. The info I am after again is Solar
production, Solar usage, Solar exported to grid, Power imported from the
grid and total power used hourly (even 15 minute increments), daily,
weekly and monthly. If you can detail products (model Numbers) and
costing as well please. Also is an electrician needed to install this.

Thanks again.


I don’t know the regulations where you are, so I can’t tell you whether you need an electrician. In the UK, because there is no direct connection to the electricity supply other than via a normal plug and socket, and the cables where c.t’s need to be fitted are normally accessible, the answer is no.

As I’ve explained various options, you need to decide, based in part on what you’re confident you can do, on which approach you want, then I can list what I think is needed.