What is the accuracy of the instrument? Now let's discuss the "accuracy" of the instrument: there is nothing to do, and learn the advantages of all the automatic nitrogen determinators in the same industry. It is found that some manufacturers have adopted the concept of "titration accuracy". This is a whim. I'll check the literature about "instrument accuracy" and get to know about "accuracy". Encyclopedia and other documents tell me: the concept of accuracy: accuracy is the closeness between the measured value and the true value. Including precision and accuracy. Accuracy characterization method: There are usually three methods to characterize accuracy. 1) Percentage of the maximum error to the true value, such as the measurement error is 3%; 2) Maximum error, such as measuring accuracy of 0.02mm；; 3) Normal distribution of errors, such as 0%~ 10% accounting for 65%, 10%~20% accounting for 20%, 20%~30% accounting for 10%, and above 30% accounting for 5%. Besides judging the importance of endpoint method, titration accuracy is the most important technical index of automatic nitrogen determinator. If the titration accuracy is high, the instrument reliability is high; If the titration accuracy is unbearable, it is not an instrument. The titration accuracy of some imported automatic nitrogen determinators is 2ul/ step and 2.4ul/ step, and that of some domestic automatic nitrogen determinators is 1ul/ step. From the definition of titration accuracy: the error of each step is 1ul, which sample should be titrated several times? The total error is clear. The error of each step is 2.4ul. Which sample should be titrated several times? What is the total error? I'm afraid to think about it. How dare you show off such a big error? Yes: ignorance? -Don't know the technical parameters of the instrument, or the concept is wrong? Meaningless-this is written casually, it doesn't matter, nobody cares anyway? Fearless.-that's me. I'm afraid you won't buy it? Titration accuracy should be expressed as a percentage. Example: Shanghai PEO automatic nitrogen determinator SKD-2000 titration accuracy: 0. 15% (for example, a sample consumes standard acid 15ml, and the maximum deviation between the real value and the titration value is 20ul). The "titration accuracy" of the above automatic Kjeldahl nitrogen determinator is the data obtained by carefully consulting the references. I hope that Chinese people will not blindly worship foreigners and copy the wrong ideas of outsiders. . . . . . Shanghai peiou analytical instrument co., ltd