Moderators: grovkillen, Stuntteam, TD-er
BertB, is it possible to extend the scheme with your options? Or what capacitors and VDR you used and where did you placed them. Its a learning aspect for me.BertB wrote:I think it is a good starting point, but some of the Chinese products do not keep the minimum safety clearance between 230 volt and 5 volt tracks.
If that is the case, it is likely there are no electrical safety issues as long as you do not attach any other sensor to the esp that has conductive elements that can be touched from the outside.
Furthermore, you probably need some capacitors on the HLK-PM01. In mine I have also mounted an electronic fuse and a VDR.
you get 6 channels current/voltage with the ADCs in MiniPro and its cheaper than going with dedicated external I2C ADC.That's exactly the power supply setup I plan to use.. 5 of the hlk modules are in the mail. Looks good!BertB wrote:This works for me:
Thanks for the Power Supply scheme.BertB wrote:This works for me:
Pleased to see that there are people looking for real solutions to do some AC current/power measurements in combination with ESPEasy.hilo90mhz wrote:I am compiling information on my project using current measurements here http://hilo90mhz.com/remote-power-monit ... surements/
I am using espEasy to send data to thingspeak that is triggering a txt message through twillo on condition met with AC current sent along in text message - it is working.
I will write up full documentation in the coming days...
Suffice to say you want to use these current sensors for your application: https://openenergymonitor.org/emon/buil ... -interface
I have integrated their emonLib library into the MiniProExtender Arduino code on an arduino pro mini - emulating the analog read output and ESPEasy doesn't know its not just straight analog read but actually formatted current data
https://thingspeak.com/channels/101562
Hello @costo, I see you are playing with the AC712 as well, and you already posed No '15 you have ordered parts and want to try current AC measurement,have you got it woking yet? Would love to learn from you.costo wrote:hilo90mhz wrote: I am waiting for a ACS712 current sensor to arrive from china, when I have it I will certainly try the library from your link too, thanx for the good info you provided.
Hi JR01,JR01 wrote:Hi, the same author on Instructables you quoted and linked to his project to get AC current smoothed to measure it, published a new / improved project now for AC hall effect measurement with Arduino. See it here http://www.instructables.com/id/Simplif ... -Using-AC/. He does not need the smoothing circuit anymore, but uses the Arduino "Filters" library. See the filters Arduino sketch here http://playground.arduino.cc/Code/Filters. Any chance we can ask dev's to include this in order to read AC current with hall effect sensors like the ACS709, or ACS712 or similar?
Code: Select all
#define DEBUG 1
/*
Measuring AC Current Using ACS712
http://physicsnet.co.uk/a-level-physics-as-a2/current-electricity/alternating-current-ac/
*/
//parameters
const int sensorIn = A0;
int mVperAmp = 89; // use 100 for 20A Module and 66 for 30A Module, 5A is 185 for 5v input voltage // use this formula Vout = Vin/2 + ((Vin/2)/Imax)*I , first set I = 0 then 1 and substract them and you get the correcct values , Imax is not the Module type for example 20A but the Imax value wich is not the same
double ADCmaxVolt = 3.3 ; // arduino has 5, nodemcu esp has 3.3, esp has 1.06
int ADCRessolution = 1024;
int Offset = 7; // because values at zero Amp have different min max
int STime = 500 ; // twice that time
//end of parameters
double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;
void setup(){
Serial.begin(115200);
}
void loop(){
Voltage = getVPP(); // peak to peak current in amperes shown in volts
VRMS = (Voltage/2.0) *0.707; //0.0707 is kinda the same as 1/sqroot(2) = 0.7071067.. // we divide peak to peak so we get Io= peak current in amperes shown in volts and Irms = Io / sqroot(2) all shown in volts
AmpsRMS = (VRMS * 1000)/mVperAmp; //now we convert voltage to amps // RMS is equal to the value of the direct current that would produce the same power dissipation in a resistive load
Serial.print(AmpsRMS);
Serial.println(" Amps RMS");
}
float getVPP()
{
float result;
int readValue; //value read from the sensor
int maxValue = 0; // store max value here
int minValue = ADCRessolution; // store min value here
int samplecount = 0 ;
uint32_t start_time = millis();
int substracted;
while((millis()-start_time) < STime) //sample for 1 Sec
{
samplecount = samplecount + 1 ;
readValue = analogRead(sensorIn);
// see if you have a new maxValue
if (readValue > maxValue)
{
/*record the maximum sensor value*/
maxValue = readValue;
}
if (readValue < minValue)
{
/*record the maximum sensor value*/
minValue = readValue;
}
}
// i do everything twice so i get a better average in the end if something peaks, could've done better but...
float result1;
int readValue1; //value read from the sensor
int maxValue1 = 0; // store max value here
int minValue1 = ADCRessolution; // store min value here
int samplecount1 = 0 ;
uint32_t start_time1 = millis();
int substracted1;
while((millis()-start_time1) < STime) //sample for 1 Sec
{
samplecount = samplecount + 1 ;
readValue1 = analogRead(sensorIn);
// see if you have a new maxValue
if (readValue1 > maxValue1)
{
/*record the maximum sensor value*/
maxValue1 = readValue1;
}
if (readValue1 < minValue1)
{
/*record the maximum sensor value*/
minValue1 = readValue1;
}
}
// Subtract min from max
substracted = maxValue - minValue - Offset;
substracted1 = maxValue1 - minValue1 - Offset ;
if (substracted < 0)
{
substracted = 0;
#ifdef DEBUG
Serial.println(" Offset too big");
#endif
}
if (substracted1 < 0)
{
substracted1 = 0;
#ifdef DEBUG
Serial.println(" Offset too big");
#endif
}
result = ( (double)(substracted) * ADCmaxVolt)/ ADCRessolution; //gets the milivolt difference betweene the values
result1 = ( (double)(substracted1) * ADCmaxVolt)/ ADCRessolution; //gets the milivolt difference betweene the values
#ifdef DEBUG
Serial.print(" Try 1 min is ");
Serial.print(minValue);
Serial.print(" max is ");
Serial.print(maxValue);
Serial.print(" Try 2 min is ");
Serial.print(minValue1);
Serial.print(" max is ");
Serial.print(maxValue1);
Serial.print(" Togethe sampled ");
Serial.print(samplecount);
Serial.print(" times in 1 sec, first result is ");
Serial.print(result);
Serial.print(" second is ");
Serial.print(result1);
Serial.print(" Together ");
Serial.print((double)(result +result1) / 2);
Serial.println("");
#endif
return ((double)(result +result1) / 2) ;
}
Well there is quite a lot of code on the internetz for DC but AC is a pain in the assdaxkamala wrote: I'm waiting for some ACS758 devices. http://www.ebay.co.uk/itm/150653947908
here you won't need to calibrate the zero value, just change the mVperAmp value I think the logic behind the code is ok... it kinda measures Irms and average I and also power usage Code: Select all
#define DEBUG 1
/*
Measuring AC Current Using ACS712
http://physicsnet.co.uk/a-level-physics-as-a2/current-electricity/alternating-current-ac/
*/
//parameters
const int sensorIn = A0;
int mVperAmp = 30; // use 100 for 20A Module and 66 for 30A Module, 5A is 185 for 5v input voltage // use this formula Vout = Vin/2 + ((Vin/2)/Imax)*I , first set I = 0 then 1 and substract them and you get the correcct values , Imax is not the Module type for example 20A but the Imax value wich is not the same
float ADCmaxVolt = 3.3 ; // arduino has 5, nodemcu esp has 3.3, esp has 1.06
int ADCRessolution = 1024;
int Offset = 1; // because values at zero Amp have different min max
int STime = 1000 ;
float Zero = 417.1; //will get zero value based on average
float PrevZero = Zero ;
int VRMS = 230 ;//europe
//end of parameters
//double Voltage = 0;
//double VRMS = 0;
double Amps = 0;
double ARMS = 0;
double Calc = double(ADCmaxVolt) / double(ADCRessolution) * double(1000) / double(mVperAmp);
void setup(){
Serial.begin(115200);
Serial.println(" Measuring Zero value!!!");
//get average
int readValue;
int sample = 0;
float sum = 0;
uint32_t start_time = millis();
while((millis()-start_time) < 200) //sample for 1 Sec
{
readValue = analogRead(sensorIn);
sample = sample +1;
sum = sum + readValue ;
}
Zero = double(sum/sample);
Serial.print(" Zero: ");
Serial.println(Zero);
//
}
void loop(){
GetValues();
//Voltage = getVPP(); // peak to peak current in amperes shown in volts
//VRMS = (Voltage/2.0) *0.707; //0.0707 is kinda the same as 1/sqroot(2) = 0.7071067.. // we divide peak to peak so we get Io= peak current in amperes shown in volts and Irms = Io / sqroot(2) all shown in volts
// It is worth noting that it is true only for a sinusoidal waveform... here it is not so we have to multply every value and then sqr the average
//Amps = (Voltage * 1000)/mVperAmp; //now we convert voltage to amps // RMS is equal to the value of the direct current that would produce the same power dissipation in a resistive load
}
float GetValues()
{
// float result;
int readValue; //value read from the sensor
int samplecountplus = 0 ;
int samplecountminus = 0 ;
int samplecountzero = 0 ;
long sumplus = 0 ;
long summinus = 0 ;
long sumzero = 0 ;
float SumSq = 0 ;
#ifdef DEBUG
int maxvalue = 0 ;
int minvalue = 1024 ;
#endif
boolean ping = true;
uint32_t start_time = millis();
while((millis()-start_time) < STime) //sample for 1 Sec
{
readValue = analogRead(sensorIn);
#ifdef DEBUG
// get min max only if you want to
if (readValue > maxvalue)
{
maxvalue = readValue ;
}
if (readValue < minvalue)
{
minvalue = readValue ;
}
#endif
// SumSq = double(SumSq) + double(sq((((double(readValue) - Zero) * double(ADCmaxVolt)) / double(ADCRessolution))))* double(1000)/ double(mVperAmp);
// Serial.print((((double(readValue) - Zero) * double(ADCmaxVolt)) / double(ADCRessolution)));
if (double(readValue - Offset) > Zero )
{
samplecountplus = samplecountplus +1 ;
sumplus = sumplus + readValue ;
SumSq = SumSq + sq((double(readValue) - double(Zero) - Offset ) * Calc) ;
}
else if (double(readValue + Offset) < Zero )
{
samplecountminus = samplecountminus +1 ;
summinus = summinus + readValue ;
SumSq = SumSq + sq((double(readValue) - double(Zero) + Offset) * Calc) ;
}
else
{
// SumSq = SumSq + sq((double(readValue) - double(Zero)) * Calc) ;
//no point doing this if it is like 0
if (ping)
{
samplecountplus = samplecountplus +1 ;
sumplus = sumplus + readValue ;
ping = false;
}
else
{
samplecountminus = samplecountminus +1 ;
summinus = summinus + readValue ;
ping = true;
}
samplecountzero = samplecountzero +1 ;
}
}
if (samplecountzero == 0)
{
samplecountzero = 1;
}
if (samplecountminus == 0)
{
samplecountminus = 1;
}
if (samplecountplus == 0)
{
samplecountplus = 1;
}
float plusavg = double(double(sumplus)/ double(samplecountplus)) ;
float minusavg = double(double(summinus)/ double(samplecountminus)) ;
float pmm = double((plusavg - minusavg)/2) ;
Amps = double(pmm * Calc);
// result = ( (((double)(sumplus)/ samplecountplus)- ((double)(summinus)/ samplecountminus)) * ADCmaxVolt)/ ADCRessolution; //gets the milivolt difference betweene the values... old style
float meansq = SumSq / (double(samplecountplus + samplecountminus)) ;
float RMSCurrent = sqrt(meansq);
#ifdef DEBUG
Serial.print(" min: ");
Serial.print(minvalue);
Serial.print(" max: ");
Serial.print(maxvalue);
Serial.print(" samples: ");
Serial.print(samplecountplus +samplecountminus);
Serial.print(" count plus: ");
Serial.print(samplecountplus);
Serial.print(" plus sum: ");
Serial.print(sumplus);
Serial.print(" count minus: ");
Serial.print(samplecountminus);
Serial.print(" minus sum: ");
Serial.print(summinus);
Serial.print(" count zero: ");
Serial.print(samplecountzero);
Serial.print(" zero this run: ");
Serial.print(Zero);
#endif
Zero = double(double(double(sumplus +summinus)/ double(samplecountplus+samplecountminus)) + Zero)/ 2; // prevent fast changes
#ifdef DEBUG
Serial.print(" avg and zero next: ");
Serial.print(Zero);
Serial.print(" plus avg: ");
Serial.print(plusavg);
Serial.print(" minus avg: ");
Serial.print(minusavg);
Serial.print(" Current: ");
Serial.print(Amps,4);
Serial.print(" RMS Current: ");
Serial.print(RMSCurrent,4);
Serial.print(" Power consumption: ");
Serial.print(RMSCurrent * VRMS ,4);
Serial.println("");
#endif
// return (double(result)) ;
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