First. Longitude and latitude meter
It is an instrument for measuring horizontal and vertical angles. By the telescope, horizontal and vertical dial and base and other components. According to the reading equipment is divided into vernier latitude and longitude meter, optical latitude and longitude meter and electronic (automatic display) latitude and longitude meter. The latitude and longitude instrument is widely used in the control, deformation monitoring and construction release and other routine measurement work. China latitude and longitude instrument series have: DJ07, DJ1, DJ2, DJ6, DJ15, DJ60 six models ("DJ" means "geodetic latitude and longitude instrument", "07, 1, 2, . ..." respectively for this type of instrument expressed in seconds for the horizontal direction of the error of a measurement back). When the special accessories are attached to the latitude and longitude instrument, it can be composed of: laser latitude and longitude instrument, slope latitude and longitude instrument and so on. In addition, there are also special gyro-latitude instrument, mine latitude and longitude instrument, photographic latitude and longitude instrument. According to the accuracy requirement of horizontal displacement monitoring, the instrument of 2 seconds or more is generally used to measure.
Due to the development of time and science and technology, the progress of the production process, the latitude and longitude meter has been gradually replaced by the total station.
Second, the level meter
Measure the height difference between two points of the instrument. By the telescope, level (or compensator) and the base and other components. According to the structure: fixed mirror level, turn mirror level, micro-tilt level, automatic leveling level. Level meter is also widely used in the control, deformation monitoring and construction of sampling and other measurement work.
China level meter series standards are: DSO5, DS1, DS3, DS10, DS20 and other models ("DS" means "geodetic level meter", "05, 1, 3 ------ are This type of instrument is expressed in millimeters per kilometer level measurement of the median height difference of the accidental median error). When the level is equipped with special accessories, the laser level can be formed. According to the requirement of vertical displacement monitoring accuracy, generally use DS1 or above level meter to measure.