Archived Forum

Your emonTx is node 10, and it sends this data:

  int power1, power2, power3, power4, Vrms, temp;

What you are reading after "OK" is byte values. Therefore:
10 0 = node 10
0 0 = power1
0 0 = power2
0 0 = power3
0 0 = power4
25 100 = Vrms = (256 * 100 + 25) / 100 = 256.25 V
0 0 = temperature

You will always receive these values (node number, 4 powers, voltage, temperature), no matter how many CTs are connected. Absent CTs and temperature sensor send values of zero.
You cannot delete 'active' inputs on emoncms. They are automatically created as soon as data is received.

Have you reset (or restarted) your emonTx after connecting the CTs? They are detected at start-up and only connected ones are read, but it still sends "0.00" even when no CT is connected.

Hi

Thanks for your reply. regarding the 7 inputs I could in the meantime figure it out as well by myself. It is as you have correctly stated the 4 inputs including voltage and temp (if used). :-)

I've read about the restart of the emontx and that the sensors must be connected before it is powerede up. I think I've followed that instruction but will give it a try again.

Is there any way to debug the emontxv3 itself? it has a network interface but I haven't found anything about the ip address.

Br

stefan

Please DON'T submit multiple copies of a post. If your comment has gone into the queue for moderation, you will see a message in your browser. All you do is waste everyone's time.

To reset/restart the emonTx V3, just press the 'reset' button next to the screw terminal block.

The V3 does NOT have a network connection. The RJ45 connector is the temperature and pulse inputs. To debug, you need a programmer (from the shop) and the Arduino IDE installed on your computer. But first, how have you installed the CT's? Have you done as instructed in Building Blocks (and the picture on the CT page in the shop)? Have you pushed the plug all the way in? The last one seems the most likely as you are getting exactly 0 for the power.

sudo redis-cli FLUSHALL 

may help to clear deleted inputs and stop them reappearing (on local emoncms)

Paul

Hi

Sorry for submitting the same post more than once. To be honest I did not see the message and was wondering why the post was not posted. I realized it just some time after.. sorry for that.

In the meantime I could get everything running. I have some values on the sensors although I'm facing already a new problem. Sensor CT1 (48A) and CT2 (39A) are returning good values but sensor three which should be showing almost the same values as CT1 and CT2 is returning a value I don't understand.

I've already tried turning the CT sensor (which just turned the values more into negative values) and swapping the sensor with CT2 for example. By swapping the sensor the value became negative on CT2 and CT3 showed the value from CT2.

Could it be that the sensor is faulty?

Thanks

Br

stefan

What country are you in? What is your power system? What are your 3 CTs measuring?
If you put all 3 CTs on the same cable, do all 3 read the same? Do they all read the correct power to within a few percent?

Hi

I live in Austria.. power system is three phase current.. currently CT1,2 and 3 are connected to one of the three phases of a circuit. I haven't tried the hint with the three sensors on one cable :-) thanks for that.. will do this tomorrow.

thanks br

stefan

The default sketch - in fact all the sketches on this site - are for a single-phase system except those that specifically have "3Phase" in the name. As long as all 3 CTs are on the same phase as the ac adapter, all should be well. If not, then you need to change to one of the 3-phase sketches.

Thx for your reply.. ok i first need to figure out what you mean with "sketch". The EmonTx is connected to a different power source than the three phase system..

to explain about what i want to do: currently we have 3 main inputs from the local energy supplier in our house. those inputs are split in parallel into several distribution circuits for different rooms. I want to monitor each of those rooms with one of those EmonTx devices. The rooms are all connected via 3 phase power (each phase not exceeding more than 100A)

Br

stefan

"Sketch" is the Arduino name for the user program that is loaded into the emonTx (as we use the same Atmel microprocessor).

You do have a 3-phase supply. If you want to monitor each room, then the emonTx V3.4 has 4 inputs - 3 the same and one designed for a much lower current but that can easily be changed by adding one resistor to the circuit board.

The "sketch" - the one that is in the emonTx when you receive it - is for a single phase only, so to monitor 3 phases you would need 3 x emonTx + 3 x ac adapter, and you would then have the power on each phase for each of 4 rooms.

Alternatively, you could use a 3-phase sketch and have one emonTx for each room. That is likely to be the best solution if you have more than 4 rooms that you want to monitor.

ahhh.. ok.. now I see what we're talking :-)

Ok i need to order the usb dongle to program a correct sketch to the emontxv3. I think I've got it now.

thanks a lot

Br

stefan

Just one word of caution: we are having trouble with the 3-phase sketch. I think that JeeLib has grown larger to accommodate the code for the RFM69CW radio and that is causing memory to be corrupted. I am working on the problem.

Which radio module do you have in your emonTx - RFM12B or RFM69CW?

Any news on this? I planned to use emontxv3 and RFM69CW on a 3phase sketch.

Thanks for your help

It's basically working but not fully tested. Watch this space (or GitHub!)

hi

sorry for the late reply but i was not in the office the last days. It's partially working. For whatever reason I have troubles with the 3rd sensor. It is nor reporting "good" values. When i cross out the sensors it is always the 3rd input - not the sensor - which is not reporting correct values. They are always to low.

So far I've not figured out why. Also Sensor 3 is always showing a value and then 0 and then again a value. Don't know where this is coming from.

Br

stefan

I assume from what you wrote earlier that you have a 3-phase supply, and that "Sensor" means a current transformer connected to your emonTx.

If it is only the number for channel 3 that is reporting varying values, you should start by checking the connection between the current transformer and the emonTx. Is the plug fully inserted, have you removed the cover and checked the wires? Is the current transformer a split-core one, and is it clipped together properly? If you exchange a 'good' input with No.3, does the problem stay with channel 3 or does it move?

The "approximate" 3-phase sketch, with slimmed down code to drive the radio module (either the RFM12B or the RFM69CW, selected in the sketch) that does not use JeeLib is now on GitHub at https://github.com/openenergymonitor/emonTxFirmware/blob/master/emonTxV3...

I do not have a 3-phase supply, so you should fully test it before relying on the readings.