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Hey everyone! I've connected the input based on this link from the building blocks: http://openenergymonitor.org/emon/buildingblocks/measuring-voltage-with-an-acac-power-adapter

I'm able to read the value from the arduino and I know you have to compute the values based on this link: http://playground.arduino.cc/Main/DirectMathVoltmeter

1) The value from analog input on the arduino needs to divide 1023 then *5 and afterwards I have to divide back the Resistors 1 & 2 to get the values before the voltage dividing. What comes after that? What about the transformer AC-AC power adapter? Shouldn't I need another math to step back up the values to get the final measurement?

2) I've looked at this link:http://openenergymonitor.org/emon/buildingblocks/arduino-sketch-voltage-and-current 

and I want to ask if it is the measurement of the phase difference of the two inputs current & voltage? 

Here is my code: 

const int analogIn0 = A0;
const int analogIn1 = A1;
int mVperAmp = 185; // use 100 for 20A Module and 66 for 30A Module
int RawCurrentValue= 0;
int RawVoltageValue= 0;
int ACSoffset = 2500; 
int Denominator = 0;
float AcVoltage = 0;
float Voltage0 = 0;
float Voltage1 = 0;
float Amps = 0;

void setup(){ 
 Serial.begin(9600);
}

void loop(){
 
 RawCurrentValue = analogRead(analogIn0);
 RawVoltageValue = analogRead(analogIn1);

 Denominator = (10000)/(130000);
 
 Voltage0 = (RawCurrentValue / 1023.0) * 5000; 
 Voltage1 = (RawVoltageValue / 1023.0) * 5000; 
 AcVoltage = (Voltage1 / Denominator ) ;
 Amps = ((Voltage0 - ACSoffset) / mVperAmp);
 
 
Serial.print(Amps);
Serial.print(", ");
Serial.println(AcVoltage);

}

If it is, how do I do the measurement on this code?