OpenEnergyMonitor

 Hi, i was wondering how to measure real power in a 3phase circuit without the mesaure of the 3 phase voltages.

I was reading the source code, and realized that the voltage readings is done at the same phase, without any phase shift compensation. That is correct?  Is it a problem or it doesen't matter? Do the calibration procedure compensates the phase shift?

Thanks

 Hello,

I'm using 3xAA batteries to power my emonTx, I dont think it's a problem, or am I wrong?

With the stability of the Tx, GLCD etc, are there any plans to create a "semi" invasive module?

Might be worth combining your experiments from http://openenergymonitor.org/emon/node/27, inspired by Jao and Guo's Powerbox into a modern equivalent? I.e a safe socket, allowing appliances to be plugged in and measured (not necessarily controlled), and reported back to the Base.

Tutus

Hi,

Today, i was unable to find an assembled emonTX in the shop.

For the emonBase, the recommandation was to get a Nanode RFX.

I bought 2 Nanode RFX , one for the emonBase, one for the emonTX.

Am I right in my choice ?? 

Yann

Also, is there an old sketch for the Nanode5 knocking around, that receives and posts the data from a one (or two) channel TX, as well as apparent power, Vrms, Irms and PF, or do I need to get a NanodeRF? 

 for Arduino ver 1, remember to read this:

Unpack the archive and rename the result to JeeLib.

Put it in the libraries folder in your Arduino sketches area.

you find the files here: https://github.com/jcw/jeelib (was getting a bit frustrated until i found out)

Hi All,

Ive recently completed a build of the EmonTX (previously using Mains Non-Invasive V3).

After looking through the various firmware options I've been using the following firmware https://github.com/openenergymonitor/emonTxFirmware/tree/master/emonTx_1CT_Voltage

as I wish to monitor both voltage and current (one CT). To do this im using a 9v transformer to measure mains voltage. However, my values are off by quite a bit.....for example the EmonTX output monitored via its serial port (real, apparent, VRMS, IRMS, supplyV)

7.59 82.53 343.41 0.24 3164

In relation to the firmware above - could anybody explain the numbers in the calibration code here...

emon1.calibration(357.6,126.5,0);
  emon1.calc(20,2000,vcc );

I think I need to substitute these for my own. Im also confused as the previous V3 firmware had declarations for the number of CT turns, burden resistor value etc. to calculate the scaling factor - none of these are mentioned in the firmware above. Thus, where my mains voltage is 240V (238V at present) the EmonTX is returning 343.41.

In addition, I have the CT connected at present to channel 1 (changed code to reflect this), however there is no wire through it at present so it cannot be reading any current. Yet however, Im showing an apparent and real power measurement. Obviously this would introduce errors into the system at times whereby voltage is being measured byt current consumption is zero or practically zero. Indeed with the above example the current consumption is nearly 0 at 0.24a but still the power calculations are off.

I am using an SCT-013-000 CT  - it came with the EmonTX kit. Anybody know how many turns is on this CT?

Thanks in advance for your time - hopefully somebody can shed some light on this - or explain how I can calibrate the EmonTX properly.

Kind regards

Gerard Gallagher

 Finally yesterday I recived the emonTX  EmonBase and FTDI adapter. I builded EmonTX, but I´m still get no success to get programed with the inteface CP2101. I downloaded the drivers from Silabs, but still can´t comunicate with the EmonTx to download Firmware. Just for troubleshooting I´m swapped the Atmega with the Arduino Uno that I have and programed on it, then backswapped to the EmonTx and seems to be working since Led is stays on fir about half a second on power up and blinks ever few secs, but I can´t debug with serial because cant get CP2101 interface cable working.

 Any ideas to get the interface working (I runing arduino IDE on MAC)

 Thanks in advance

do you have info for the us market please

I am in the States and I have ordered the CTs but I am confused on which jacks to order. The jacks that you have listed are from European distributors. When I look through US distributors I do not find those exact jacks.

I am wondering, will any phono jack work? I got some jacks at Radio Shack but they do not seem to work. So I am confused on what the right jack connectors to get for the CTs.

Thanks,

Paul.

Al working and sending to the Base.
Question 1 - if i connect power via the USB and batterry, will the battery cut in quick enough to avoid much data loss if USB power is cut?

Question 2 - looks like the pulse counter is using interrupts - how easy is it to substitute one of the CT circuits for a second pulse reader?

I've been absent for a while ... you've been busy!  The new design looks great.

Here in the US I needed 4 CTs to measure my home + solar output; 2 CTs on the mains and 2 CTs on the solar feed.  Is there room for another CT input channel?

-Eric

Today I found you website and this project: absolutely great !!

We work on Apps for photovoltaic systems. We would like to test these devices.

How to start now?

thanks a lot

Inspired by your project I did a home heat pump monitoring system with web UI to monitor the results(something similar to opencms) check it out: http://dl.dropbox.com/u/18771283/heat%20pump.png

One of the ideas I have is to have the emontxs poll the emonbase for configurations (calibration values and so forth) and then have the emonbase equipped with a web UI so that these configurations may be done online and pushed to emontx-s. That should make this whole thing more accessible as users won't need FTDIs to configure it.

Keep up the great work!

I was thinking on ways to cut costs even further, a XBEE does have A/D inputs and can transmit power and 6 temperature readings to a XBEE-enabled NaNode if I am not mistaken.

How does that sound?

I am interested in this new version, when they intend to publish it.
Best regards from Guatemala, Central America