Can someone please explain Measurement, input, offset and slope of a pH transmitter. My transmitter gives slope in the range of 12-25% mA. What does that mean? How do I compare it with 92-102% original range for any pH probe slope??
Offset and slope are the parameters of a linear regression function between pH and potential (voltage). Briefly, high pH means low activity of protons, thus low voltage. This is why slopes are negative.
The slope value is specific for your pH probe. A slope value of -60 mV means that the voltage drops by 60 mV per 1 pH unit increase. Unstable and low slopes indicate probe aging or bad handling (wrong solution filled in?). Please consult the manual of your probe for details.
See also: http://us.mt.com/dam/MT-NA/pHCareCenter/pHTheoryGuide.pdf
Hi, Thomas. Thanks for the quick response. Can you tell me how to calculate slope when its measured using 4-20 mA scale?
Could anyone provide the reference of formula for calculation of pH Slope?
(voltage(mV) difference / pH difference)/Theoretical voltage(59.16mV)= Slope
- Badges
- Science topic
- Similar topics
- Biological Science
- Biochemistry
- Biochemical Techniques
- Analytical Chemistry
- pH