Forum >ec sensor calibration
ec sensor calibration
apitta 2016-05-31 19:26:49 13553 Views6 Replies hello guys,
I am studying the documentation of ec sensor (http://www.dfrobot.com/wiki/index.php/A ... KU:DFR0300) but until now I couldn't understand how can I update code after using calibration solution.
I am reading a value different of the solution even considering the temperature.
I also compared to another ec sensor (hm digital com-80) and I can see that the reading is not accurate.
So, what are the steps to get the sensor calibrated?
Using the sample code, I can read the following information:
dry sensor > analog 0-1; voltage 0-4mV; temperature 20.37; ec "no solution"
1413 us/cm > analog 44-45; voltage 214-219mV; temperature 23.33; ec 1.48-1.52 ms/cm
12880 us/cm > analog 350-366; voltage 1728-1787mV; temperature 20.81; ec 12.15-12.59 ms/cm
I reviewed formulas many times but I am stuck maybe because I don't have enough knowledge of physics and mathematics.
Can you share any information about that?
Another doubt that I have is, how the constants of code below were calculated/defined?
if(CoefficientVoltage>149 && CoefficientVoltage<3301) {
if(CoefficientVoltage<=448)
ECcurrent=6.84*CoefficientVoltage-64.32; //1ms/cm<EC<=3ms/cm
else if(CoefficientVoltage<=1457)
ECcurrent=6.98*CoefficientVoltage-127; //3ms/cm<EC<=10ms/cm
else ECcurrent=5.3*CoefficientVoltage+2278; //10ms/cm<EC<20ms/cm
ECcurrent/=1000; //convert us/cm to ms/cm
}
best regards,
Alexandre Pitta
I am studying the documentation of ec sensor (http://www.dfrobot.com/wiki/index.php/A ... KU:DFR0300) but until now I couldn't understand how can I update code after using calibration solution.
I am reading a value different of the solution even considering the temperature.
I also compared to another ec sensor (hm digital com-80) and I can see that the reading is not accurate.
So, what are the steps to get the sensor calibrated?
Using the sample code, I can read the following information:
dry sensor > analog 0-1; voltage 0-4mV; temperature 20.37; ec "no solution"
1413 us/cm > analog 44-45; voltage 214-219mV; temperature 23.33; ec 1.48-1.52 ms/cm
12880 us/cm > analog 350-366; voltage 1728-1787mV; temperature 20.81; ec 12.15-12.59 ms/cm
I reviewed formulas many times but I am stuck maybe because I don't have enough knowledge of physics and mathematics.
Can you share any information about that?
Another doubt that I have is, how the constants of code below were calculated/defined?
if(CoefficientVoltage>149 && CoefficientVoltage<3301) {
if(CoefficientVoltage<=448)
ECcurrent=6.84*CoefficientVoltage-64.32; //1ms/cm<EC<=3ms/cm
else if(CoefficientVoltage<=1457)
ECcurrent=6.98*CoefficientVoltage-127; //3ms/cm<EC<=10ms/cm
else ECcurrent=5.3*CoefficientVoltage+2278; //10ms/cm<EC<20ms/cm
ECcurrent/=1000; //convert us/cm to ms/cm
}
best regards,
Alexandre Pitta
2016-06-08 23:15:40 100us/cm is within the allowed error apnge of this pH sensor (according to the specification), any way, it should be better after calibration. Looking forward to your update. Leff
Leff 2016-06-04 10:35:43 Hi Leff,
the difference between hm digital and dfrobot ec sensor is around 300 us/cm.
my point of interest is around 1500 us/cm and 2500 us/cm.
I am going into further tests and until the next week I will report my results here.
contact me any time you wish.
best regards, apitta
the difference between hm digital and dfrobot ec sensor is around 300 us/cm.
my point of interest is around 1500 us/cm and 2500 us/cm.
I am going into further tests and until the next week I will report my results here.
contact me any time you wish.
best regards,
apitta 2016-06-04 01:54:54 Very thankful that your follow-up and pleasure to help.
yes, I am in DF, we will update the wiki later on. For now, I've attached it as a FAQ. Leff
yes, I am in DF, we will update the wiki later on. For now, I've attached it as a FAQ.
Leff 2016-06-03 19:53:27 Hi Leff,
I really appreciate your reply!
I am glad to you!
I am doing an automation process using EC readings as a point of decision, so I need high accuracy to manipulate acid or base in my water tank.
the water is being used in a hydroponic system for greenery.
do you work in the dfrobot?
if yes, I really recommend that those information would be included in the wiki page because it explains in much more detail how it works.
I think it could be helpful to new and current users.
best regards, apitta
I really appreciate your reply!
I am glad to you!
I am doing an automation process using EC readings as a point of decision, so I need high accuracy to manipulate acid or base in my water tank.
the water is being used in a hydroponic system for greenery.
do you work in the dfrobot?
if yes, I really recommend that those information would be included in the wiki page because it explains in much more detail how it works.
I think it could be helpful to new and current users.
best regards,
apitta 2016-06-02 07:34:06 Hi Leff,
before I buy this sensor I had one from HM digital like this:
http://www.tdsmeter.com/products/com80.html
I am using this to compare measures.
best regards,
Alexandre Pitta apitta
before I buy this sensor I had one from HM digital like this:
http://www.tdsmeter.com/products/com80.html
I am using this to compare measures.
best regards,
Alexandre Pitta
apitta 2016-06-02 02:04:36 Hi apitta,
That wiki is really hard to read to figure out how to calibrate the code, and without any example showing how to.
So, did you bought two EC meter, the reading of one is very wrong from another? Because as claimed in the wiki that even the sensor is not been calibrated, the reading should be correct, only with slight error. Leff
That wiki is really hard to read to figure out how to calibrate the code, and without any example showing how to.
So, did you bought two EC meter, the reading of one is very wrong from another? Because as claimed in the wiki that even the sensor is not been calibrated, the reading should be correct, only with slight error.
Leff 