It is well known that the compensator is made of a metallic material and a glass material, and these materials are affected by the temperature and cause a slight change in the compensator, resulting in a change in the angle of the i. The temperature-compensated instrument often does not meet the national standard GB / T 10156-4997. In the figure below, the green area in the red line boundary is the qualified area of the compensator change when the temperature changes (the enterprise standard stipulates: ± 0.5 "/ degrees Celsius.) In the red thick curve, A is the temperature Compensation level i angle change curve. DSZ2 has been added with temperature compensation device, the use of temperature compensation device on the i angle with the temperature changes in the amount of correction, as shown in the green thick line B is the compensated i angle curve, which So that the instrument in the temperature changes under the harsh conditions can meet the requirements of the use of long-term deformation observation is particularly applicable.