Analog TDS Meter

Account cancelled 2018-05-25 08:22:21 1305 Views1 Replies
Could someone explain this line from the Analog TDS Meter example code?
Code: Select all
tdsValue=(133.42*compensationVolatge*compensationVolatge*compensationVolatge - 255.86*compensationVolatge*compensationVolatge + 857.39*compensationVolatge)*0.5; //convert voltage value to tds value

Is there a formula it's based on? What are the numeric values?

https://www.dfrobot.com/wiki/index.php/ ... U:_SEN0244

2018-05-30 13:46:45 This formula is got from experiment, by measuring several examples and get the voltage and TDS value, you can match a equation between voltage and TDS value. robert.chen