Power analyzer using arduino

[iffi444]

As input range of NI myDAQ is 10v,and we step down and conditioning the phase supply according to it but during analyzing on labview how will it be present as 220V(single phase Vrms in Pakistan)

[hrh1818]

You need to use an algorithm to calculate the RMS value of a set of readings an then use a conversion factor to convert MyDaq measurements to power line values.

hrh212

[iffi444]

Can you please explain a bit more please

[Nathan_B.]

What part don't you understand?

[iffi444]

Calculation of Vrms And current in Labview if daq input to analoge pins specified to 10v

[hrh1818]

Here is the information I posted in an earlier message in this thread.

RMS means root mean squared.  Hence first square each voltage reading.   Next calculate the sum of all of the voltage squared readings.  Next divide the sum of voltage squared readings by the number of readings to find the mean value.  Last take the square root of the mean value to find the RMS value.   Measurement of the voltage signal must be made at regular intervals and for an integer number of periods of the input signal.

The first formula on the following web page shows the formula for calculating the RMS value.

<https://en.wikipedia.org/wiki/Root_mean_square#Definition>

To make RMS measurements you need to sample the signal for an integer number of periods.   Use the following formula to calculate sample rate.

samples per second =  number of samples  / N*T

Number of samples  = number of data points you want to use to calculate RMS values.

T is the period for one cycle.  T = 1/50 for 50 cycles per second power and 1/60 for 60 cycles per second power.

N is the integer number of periods.

hrh212