Community
OpenEnergyMonitor

Community

EmonTx for 3 phase + 1 phase

Tags: #<Tag:0x00007f6e0f7c9370> #<Tag:0x00007f6e0f7c9230>

Hi, I am thinking on using One emonTx for measuring a 3 phase (without available neutral) Main power connection (this is the One that I get from the power supplier), and also the connection to the heating system which is one phase. I need 4 cts, which EmonTx apparently handles.
Can I do both with a single emontx. The result should be measures of the total power consumption in my house and an specific measure of my heating expenses. I dont really nead real power on each phase, I accept apparent power.
Do I need to code something for this setup?
Thanks!

One emonTx should be able to do that, provided that you are able to accept the inaccuracy of apparent power, but also any errors due to voltage imbalance between the phases.

You will need to do a little coding. EmonLib produces all the values, but the default sketch only sends real power. You’ll need to edit that so that it sends apparent power: all that needs to be done is to replace realPower with apparentPower. And you’ll need to scale the outputs by 1/√3 (or just the voltage before it’s multiplied by the currents) because you’ll be measuring line currents but line-line voltage.

I don’t recommend that you include the expense calculation in the emonTx, as it will mandate reprogramming every time the charges change.

Thanks Robert! It makes sense. I´ll post the config after i get it running. Have a nice day!

1 Like