Hi, here I am again…
I’ve test your solution in two way:
First I ‘ve done a 3 turn for the primary with a 4mm2 wire and change the calibration constant from 111,1 ( i have a burden resistor of 18 ohm and this value is a starting point of the ‘Learn’ and however correct during a test of 1000W resistive load) to 111,1 / 3 = 37,03.
The error scaled down but the power factor is distant from 1.0 .
Second test I’ve tryed with 10 turns and a calibration of 1/10 but a wire of 1,5mm2 with no load or max load of 20-30W of led lamp. With no load I have a power result o 3,5W and applying some load about 150W the reading is correct.
I don’t want to try more load because I need a correct dimension of wire, 1,5mm2 is too little, 4 is more correct for a max of 16A .
Now my question is, if the ratio between real power and apparent Power is near 1.0 with more than 100W with only 1 turn and if I see a correct real power with 10 turns and no load or little load but the cos Fi is completely wrong (0.06!), considering the cos Fi a phase displacement from real power and apparent power usually present during inductive load or capacitive load, what I have to consider correct? The real power when I have a load that I know also if the power factor is wrong? The CT rappresent an inductive load if the load is too little ? The problem is only the sensibility of the CT? I have to settle for this error and therefore I can not consider the loads below 50W as correct readings? or find sensors that allow me to wrap more coils of cable of adequate size? amplifying the output value from the CT would improve the accuracy or make the reading scale more raw?
From the link that I have posted the problem with low load is only the false reading of the sensor that make a wrong reading during the calc of the measuring…
thanks for your patience …and please sorry for the amount of question!!
Thanks