The main factor causing error bimetallic thermometer

Bimetallic thermometer is expansion type thermometer, the main factor causing error: ( 1) Thermometer should be in the temperature of - environmental conditions 40° C ~ + 55° C, relative humidity is not more than 85% under the conditions of use, otherwise it will cause greater error. ( 2) Mechanical damage in use, the instrument has been heavily impact and collision, easy to cause the protection tube deformation, thus affecting the normal work caused by the error of measuring mechanism. ( 3) Fatigue damage after long time use, can make the performance of the sensing element changes caused by the error. ( 4) The depth of the insert depth of medium thermometer inserted into the medium must ensure that is greater than the length of the sensing element, if the insertion depth will cause the error.