Hi, I installed the EmonPI system to monitor the home consumption. I am the Vrms of calibration of approximately 15V. I wanted to know if there was a way to calibrate the reading ... this drawback, of course me wrong values also on the power that I am actually using.
Hoping for your help greet and thank
Luca
Re: Vrms incorrect
The easy way is to edit your emonhub.conf file. You can do this from the web interface.
In the file, find a section like this:
[[5]]
nodename = emonpi
[[[rx]]]
names = power1,power2,power1pluspower2,vrms,t1,t2,t3,t4,t5,t6,pulsecount
datacodes = h, h, h, h, h, h, h, h, h, h, L
scales = 1,1,1,0.01,0.1,0.1,0.1,0.1,0.1,0.1,1
units = W,W,W,V,C,C,C,C,C,C,p
"vrms" is the fourth item, therefore you change the value of the 4th number in "scales". If you want to change the value you see by 10%, "scales" will become:
scales = 1,1,1,0.011,0.1,0.1,0.1,0.1,0.1,0.1,1
Re: Vrms incorrect
I thank you, I set the value as you suggested and put 0011 but the end result is that I was reading 2270V...O_O
in order to read the correct tension I had to set the value 0.0099 .... just that I noticed something, since I changed the voltage value remains stable at 227.70V, how is it possible?
Thanks in advance for all the help
Luca
Re: Vrms incorrect
You did not say what value you were reading and what the correct value was, therefore I could not calculate the correction. That is why I wrote: "IF you want to change the value you see by 10%, "scales" will become ... 0.011"
If the value does not change, I think you might also have this problem.
Re: Vrms incorrect
@ Robert Wall ... Can you confirm that this only affects the Vrms displayed and not taken into the wattage calculation?
Re: Vrms incorrect
That, the scaled value, is what emonHub passes into emonCMS. So I am reasonably certain, but not 100% sure, that you will need to scale the power and energy values likewise (assuming that your current calibration is correct, or taking that into account also if you think that too is wrong).
If you want to correct the voltage calibration at source, you will need to carry out the standard calibration procedure, but the sketch you edit is in the Raspberry Pi; compile the sketch and them load it into the emonTx inside the emonPi via the serial link. It is a complicated procedure and the instructions are in the hardware Wiki.
Re: Vrms incorrect
Yes I have corrected the voltage in the *.ino file, compiled and flashed the atmega with the altered hex but when there are updates github complains about the files containing local changes and won't update the hex. I have to delete those local files that I have changed, update to the latest, calibrate and flash again :-(
There must be an easier way...
Voltage read with a calibrated multimeter is 240V, emonpi reads 266V.
Re: Vrms incorrect
I don't understand GitHub, so I can't help you there. Bill Thomson recommended "Git Succinctly", by Ryan Hodson, but I've yet to find the time to read it!
It used to be available from https://cld.pt/dl/download/e1946c4f-499c-4961-b63a-179c2fb3526e/Livros%2520Linux/GIT_Succinctly.pdf
Which ac adapter are you using? That's possibly the reason for the high voltage.
Re: Vrms incorrect
Could you be experiencing the same issue as this thread:
http://openenergymonitor.org/emon/node/12188
Could you try an emonPi update: Admin > Update from local Emoncms