Topcon GPT-3002LW Total Station

Total stations, such as the one shown here, have both a theodolite and an electronic distance measuring instrument. Used today by the National Geodetic Survey, these highly accurate total stations allow distance and angle measurements to be taken using just one instrument. Weighing in at less than 20 pounds, total stations are slightly more portable than the 200- or 300-pound theodolites of the early 1800s!

Topcon GPT-3002LW Total Station

The rapid evolution of electronic technology in recent years has led to a corresponding evolution in theodolite technology. Digital readouts have replaced micrometer microscope readings, data collectors plus software have eliminated the need for a recorder, and Blue Tooth technology provides a wireless system.

The crews of the National Geodetic Survey's Aeronautical Surveys Program currently use the Topcon GPT-3002LW total station shown in the photo for airport surveys. Total stations are so-called because they incorporate a theodolite and a laser-based electronic distance measuring instrument into one instrument. By combining simple push-button systems with digital readouts and data collectors that eliminate recording by hand, total stations allow for rapid and accurate observations.

The GPT-3002LW has an angle accuracy of two arc seconds. The entire total station unit is 13.2 inches high, 7.2 inches wide, and 6.9 inches long. The entire unit, including the carrying case, weighs 18.3 pounds. Compare that to the 300 pounds of Ferdinand Hassler's Great Theodolite!

  • Instrument Shown: Topcon GPT-3002LW total station
  • Location: Norfolk, Virginia
  • Manufacture Date: 2006
  • Dates of Use: Current
  • Photo date: 2006

Works Consulted

Intec Marketing Services Sdn Bhd. (2006). Topcon Total Station. Retrieved on August 21, 2006, from:

Related Web Sites:

National Geodetic Survey