Inputs Data

I had a question about config inputs

I have

•1 X Clip-on CT sensors (the emonPi can accept up to two CT sensors; one is included as standard with the emonPi)
•1 x AC-AC voltage sensor adapter (optional but highly recommended)

•1 x USB 5V DC PSU

but in my inputs appear

a key with name
power1pluspower2 whit the same value than power1
vrms whit the value of ACAC voltage

I chose the power1 input to create the feeds

This config its ok ?

If I put the CT Sensor on a Neutral 3-4mm cable this would affect the metric ?
When is necessary Calibrate ?


If you have no CT connected to input 2, power2 will be zero, power1pluspower2 = power1 + power2, therefore power1pluspower2 will of course be the same as power1.

If you have a single phase installation, the neutral current must be the same as the line current (unless there is an earth fault present, or a connection to another circuit or supply, which would also be a fault), therefore you should see the same readings. Note that for the sign of real power to be correct, the CT faces the opposite way when on the neutral conductor. If you have a two- or three-phase installation, neutral current is the vector sum of the line currents (faults excepted of course) and is almost certainly not the current you want to measure.

If the values you see are not accurate, then it might be necessary to carry out the calibration procedure. Unless you think there is a need to adjust the phase error compensation, the easiest place to apply the calibration correction is in the emonhub.conf file, which you can do from a web browser. Adjust the value of the multipliers in “scales = …” for Node 5 until the emonPi reads correctly. Calibrating the voltage in emonHub will NOT affect the power calibration. You can find full details in Resources > emonHub > Configuring emonHub.

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