How to understand the precision of the bimetallic thermometer?

Bimetallic thermometer are familiar with it is a professional measurement of low temperature field instruments. Its parameters are the size of the dial, the structure of the installation, the length of screw tooth size, heat pipe and precision, etc. Other parameters are well understood, the average person on the parameters of the bimetallic thermometer is not very understanding, the following will introduce the precision of the bimetallic thermometer! The precision of the bimetallic thermometer is refers to the error of the temperature range, and high precision table prices would be higher precision generally poor watch some, bimetallic thermometer manufacturing good after will test and calibration in the temperature test equipment, because the test equipment is electronic control equipment, in the process of heating or cooling, there will be instructions on drift, coupled with the effect of the ambient temperature on the temperature you will need to make some compensation, temperature compensation scope is a typical range is smaller than working temperature range, work within the scope of the bimetallic thermometer will surely achieve its performance index, temperature affects the output from the two aspects, one is zero drift, 2 it is to affect the full scale output. Such as a full range of + / - / C, X % + / - reading X % / C, in the full range of + / - beyond the temperature range X %, within the scope of temperature compensation + / X % of reading, without these parameters, will lead to the change of the uncertainty in the used temperature transmitter output is caused by pressure changes, or caused by the temperature change. Temperature influence is to understand how to use the most complicated part of the transmitter, the precision of bimetallic thermometer need how much? Decision accuracy are: nonlinear, refund hysteresis, repeatability, temperature, zero offset calibration, temperature but mainly by the influence of nonlinear, refund hysteresis, repeatability, accuracy is higher, the higher the price.