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Which sketches are you trying to run? The emonTx V2, the emonTx V3 and the emonTx Shield are all different and each has their own family of sketches. What voltage do you read? Bear in mind all the sketches normally expect the UK/European mains voltage adapter to be used, so if you are using a different adapter, the voltage calibration constant in the sketch will be wrong. There is a page in Building Blocks that explains the theory of calibration and how to calculate the approximate value of the constant.

Whether your c.t's will work depends on whether they will fit around your fatter cables. If they fit and close up correctly, they should be fine, provided that the maximum current you want to measure is less than their maximum rating.

Thanks for the fast reply!

i am using from here :

https://github.com/openenergymonitor/emonTxFirmware/tree/master/emonTxSh...

The following sketch:

https://github.com/openenergymonitor/emonTxFirmware/blob/master/emonTxSh...

Here is a sample of what i get:

emonTX Shield CT123 Voltage Serial Only example
OpenEnergyMonitor.org
28501.55 0.00 0.00 0.00 458.36
769.55 0.00 0.00 0.00 269.58
30.51 0.00 0.00 0.06 261.36
1.84 0.00 -0.16 0.22 261.73
-4.01 0.00 -0.00 0.07 261.61
-0.10 -0.21 0.13 0.00 261.78
-4.45 0.00 -0.00 0.00 261.52
-0.54 0.00 -0.14 0.00 262.25
-1.74 0.00 0.16 0.03 261.48
0.25 0.39 -0.00 0.00 261.41
-0.61 0.22 0.22 0.00 262.51
-8.06 0.01 -0.00 0.00 262.55
0.94 0.00 -0.00 0.19 261.78
-0.02 0.00 -0.00 0.00 263.05
-2.34 0.00 -0.00 -0.22 262.25
-3.32 -0.22 0.06 -0.22 262.25
0.79 0.22 -0.00 0.22 262.07
-5.06 0.00 -0.00 0.00 263.06
-4.92 -0.22 -0.00 -0.17 262.03
1.46 -0.08 0.19 0.00 262.21
1.68 0.00 -0.00 0.43 261.83
-0.54 0.00 -0.00 0.01 263.34
-0.20 0.05 -0.00 0.00 262.22
-5.00 0.01 -0.41 0.00 262.72
0.72 0.21 -0.19 0.00 262.19
-1.12 0.22 -0.00 0.00 262.39
-0.89 0.00 0.22 0.00 262.46
-0.38 -0.22 -0.05 0.00 263.57
-3.54 0.22 -0.02 0.04 263.87
-1.88 0.00 -0.19 0.01 262.62
-2.47 0.00 -0.01 0.00 263.00
-1.41 0.00 0.10 0.00 262.76
2.07 -0.22 0.08 0.10 262.33
-3.00 0.00 -0.10 0.01 262.84
-4.91 0.00 0.22 0.22 264.17
0.58 0.02 -0.00 0.01 262.75

I gotta take a look at the calibration you are talking about.

I am just making sure that all i need other than the calibration is one CT clamp thats  it (i guess for every Phase)

so i see 5 different numbers each raw.

the last one should be my Vrms iguess and the first one my power since i use CT1 input only correct?

Thanks any help or hint appreciated :)

If you look at the sketch, the output is generated by Serial.print(....) statements. You can guess most of them from the name of the variable. The voltage is the last figure, and it looks about what I'd expect with the 'wrong' voltage transformer. Changing the calibration constant (follow the instructions in the Building Blocks article) will put that right. The wildly wrong numbers the first few times are as a result of the software filters settling - ignore them.

But you mention "every Phase". The Shield is only designed for single phase, and the sketch is only single-phase, because multi-phase systems are practically unknown in domestic installations in the UK. Our single phase always has just one line and an earthed neutral (TN-S or TN-C-S), not the two lines centre-tapped to earth that you have. If you have either a split supply or a 3-phase setup, you need to carefully think about what you need to measure, and use an appropriate sketch.

hello Robert it makes sense now. I will follow the directions on calibrating and i will post results soon.

So out of curiocity, 2 more questions:

What is the red LED indicating on the board?

Why do we have 4 CT sensor inputs on the board? I would think each one was for one phase and an extra more? But if it is for a single phase only isnt 1 CT sensor enough?

Also i might be wrong about the two phases.

What i see on my electric panel is 2 cables leaving the meter and go to the distribution board. I thought it is 2 phases, but i might be wrong. the was the panel is there are breakers on left and right so it might be split because of this. There is only 1 main breaker so i guess that means it is a signle phase?

I am not an electricial, would it be ok to test for continuity between these two lines? If it beeps its the same thing, if not, they must indeed be two different phases (which i doubt)

Thanks again for the answers

Ok following building block s and trying to get the voltage right (using CT1) I am in the lines:

// (ADC input, calibration, phase_shift)
  ct1.voltage(0, 137.2, 1.7); <--- Changed this is 137.2 and now i read like below
  ct2.voltage(0, 300.6, 1.7);
  ct3.voltage(0, 300.6, 1.7);
  ct4.voltage(0, 300.6, 1.7);

emonTX Shield CT123 Voltage Serial Only example
OpenEnergyMonitor.org
13070.11 0.00 0.03 0.00 209.33
338.15 0.00 -0.01 0.23 123.07
15.82 0.00 -0.06 -0.42 118.84
1.75 0.00 -0.00 0.04 119.36
-1.64 0.00 -0.00 -0.10 118.88
-1.25 0.00 -0.00 0.00 118.87
0.95 0.00 -0.00 -0.10 119.00
0.32 -0.16 -0.00 0.00 118.74
1.38 0.22 0.17 0.00 119.45
-1.10 0.00 -0.00 -0.03 119.22
-2.85 0.16 0.01 0.00 118.68
-1.45 0.00 -0.00 0.00 118.75
-1.19 0.00 -0.00 0.00 118.54
0.89 0.07 0.44 -0.02 119.37
-0.58 -0.17 0.07 -0.18 118.85
-1.28 0.00 -0.00 0.01 118.91
-2.92 0.00 -0.00 0.00 119.12

Which is correct, my multimeter reads from 118.9 to 119.3.

What about the other numbers on the sketch? For example

ct1.voltage(0, 137.2, 1.7) 0 is the ADC input (i guess i leave that to 0, then the second one i changed and the third value is the phase shift, is that changeable if yes to what?)

Ok continuing to the rest....

I cannot find how i can show the current i am measuring with this sketch and the sketch links on the building blocks pages take me to a 404 page :(

Also i do not understand on step 1 on procedure:

"Load one of the demonstration sketches from emonTxFirmware: emonTx_CT123 if you only have current inputs or, if you are using a voltage input, emonTx_CT123_Voltage"

Whats the difference on only current inputs or voltage inputs? I thought i am measuring both?

Kinda stuck here, waiting for answers : ) thanks again so much

and one last question for now:

is there anyway i can calculate the Hz? It should be around 60Hz for us but i would like to know the real number

As always thanks!

What is the red LED indicating on the board?  Whatever you wish!  By default - that a value has been sent by radio.

Why do we have 4 CT sensor inputs on the board? So that you can monitor 4 separate feeds.

What i see on my electric panel is 2 cables leaving the meter and go to the distribution board. Look at the 3-Phase Power article in Building Blocks. There's a picture of a UK single phase and a 3-phase meter there. What does it say on your meter? If you have only two cables, they are most probably single core, Line and Neutral, and it's single phase.

I am not an electricial, would it be ok to test for continuity between these two lines?  NO. If the circuit is live, at best you might damage your meter. At worst, you might get a severe electric shock and very serious burns, or even kill yourself. If the circuit is dead, the test would probably mean nothing anyway. If you are not absolutely sure that what you are doing is safe, do not mess with mains electricity.

Also i do not understand on step 1 on procedure:  You can use the emonTx with or without the voltage adapter. With the old emonTx V2 you use one sketch if you use the adapter, and the other if you do not. The emonTx V3 sketch automatically senses the voltage adapter, so you can use the default sketch.  Current is being measured, it is just not being printed to Serial or being sent by radio. The current is available as ct1.Irms (etc) after a call to calcVI(...) or calcIrms(...), so you need to add a Serial.print(...) statement and/or add the current into the PayloadTX (and of course copy the value across too, something like "emontx.current1 = ct1.Irms;")

Whats the difference on only current inputs or voltage inputs?  If you measure only current, you can only estimate apparent power (VA) from the supposed voltage of your supply and the supposed power factor of your combined loads. If you measure the voltage as well, you know the voltage and you can calculate real power directly.

phase shift  The instructions to adjust that are part of the calibration procedure. Follow those instructions.

is there anyway i can calculate the Hz  A few days ago somebody posted a method that you can add to emonLib that times the length of a cycle to calculate frequency. You could search to find that and try it.

Hello takissd,

I'm in the US too, and from your description, it sounds as if your wiring is the split-phase 120-0-120 configuration typical of US residential electrical service. i.e.120 volts from either leg to neutral and 240 volts across both legs.

Regards,

Bill

But Bill, takissd says there are two wires, and you are describing a 3-wire system.

Takissd, to test this, you can measure the voltages that Bill describes. If you are not confident that you can do this in complete safety, don't attempt this. If you can't identify the neutral conductor, measure each line to ground (or earth as we call it).

hello all, thanks so much for the  responses. I will follow your instructions and go from there and follow up.

Thanks again