What is a total station? How it works, accuracy and price
Key takeaways
- A total station measures angles and distances in one pointing and converts them into coordinates and heights in real time.
- Distance accuracy is quoted as a fixed part plus a part per million (ppm) of the distance, so error grows slowly with range.
- Reflectorless, Android, robotic and scanning models extend the basic instrument for different jobs.
- Reliable results depend on the whole kit, including tripod, tribrach, prism and pole, and on regular field checks.
- Total station price depends mostly on angle accuracy, reflectorless range, software and automation.
What is a total station?
A total station is a surveying instrument that measures angles and distances electronically and computes the position of the point being measured. It is the standard tool for land surveys, building layout, road works and deformation monitoring.
The name reflects that one instrument does the "total" job once split between a theodolite, a distance meter and a field calculator. If you are coming from angle-only instruments, our comparison of the theodolite vs total station explains the step up.
A total station survey typically runs from a known control point. The instrument records every observation digitally, so field data moves straight into drafting and design software without manual transcription.
How does a total station work?
A total station works by measuring three values to each target, the horizontal angle, the vertical (zenith) angle and the slope distance, and converting them into coordinates. Everything else is calculation.
Angle measurement
Glass circles with coded patterns are read by electronic encoders as the telescope turns. A dual-axis compensator measures any residual tilt of the instrument and corrects the angles automatically.
Distance measurement
The EDM emits modulated infrared or visible laser light. Phase-shift EDMs compare the phase of the returned signal with the emitted signal; pulse EDMs time the round trip. A prism returns a strong signal over kilometres, while reflectorless mode uses the weak return from walls or ground over shorter ranges, as covered in reflectorless total stations and EDM.
Coordinate calculation
With slope distance S and zenith angle Z, the horizontal distance is S × sin Z and the height difference is S × cos Z, plus instrument height minus target height. Combining horizontal distance with the bearing from the backsight gives easting and northing for every point.
Total station accuracy: what the specifications mean
Total station accuracy is specified separately for angles and distances. Both contribute to the final position error, and both depend on setup quality as much as on the instrument.
Angle accuracy is given in arc-seconds, such as 1", 2" or 5". An angular error of 1" displaces a point by about 0.5 mm at 100 m, so a 2" instrument contributes roughly 1 mm of lateral error at 100 m. Distance accuracy is written as a + b ppm: a fixed error plus b millimetres per kilometre.
| Distance to target | 2 mm + 2 ppm (prism) | 5 mm + 3 ppm (reflectorless) | Lateral error from 2" angle |
|---|---|---|---|
| 50 m | 2.1 mm | 5.2 mm | 0.5 mm |
| 200 m | 2.4 mm | 5.6 mm | 1.9 mm |
| 500 m | 3.0 mm | 6.5 mm | 4.8 mm |
| 1,000 m | 4.0 mm | 8.0 mm | 9.7 mm |
The middle columns match the published distance specifications of our TS1000 total station. In practice, centring errors of the instrument and prism pole, atmospheric conditions and pointing often add more error than the specification, which is why careful setup matters.
Types of total station: electronic, reflectorless, Android and robotic
All modern instruments are electronic total stations, but they differ in how they measure, what software they run and how much automation they offer. Choose by the work you do most.
| Type | Key feature | Best for | Example |
|---|---|---|---|
| Standard (prism) | Long prism range, keypad software | Control, traverse, topographic work | TS1000: 7,500 m single prism |
| Reflectorless | Measures surfaces without a prism | Facades, inaccessible points, as-built | STS2: 1,000 m reflectorless, laser plummet |
| Android total station | Touch screens and app-based field software | Mixed survey and layout crews | STSA9: dual 5" touch screens, 1,500 m reflectorless |
| Robotic (automated motorized) | Servo motors and prism tracking, one-person operation | High-volume layout, monitoring | See robotic guide |
| Scanning total station | Adds 3D scanning to total station functions | Combined survey and point cloud capture | — |
An automated total station, or automatic total station, turns and locks onto the prism itself. Whether that is worth the extra cost is discussed in robotic vs manual total station. You will also see the term GPS total station, which usually means a workflow combining a GNSS RTK rover with a total station on the same coordinate system, so crews use GNSS in the open and the total station where satellites are blocked. Our GNSS RTK vs total station guide compares the two.
Total station survey equipment: what is in the kit
A total station is only as accurate as the equipment around it. A working kit for one crew typically includes the items below.
- Tripod: a stable wooden or aluminium tripod with a 5/8" × 11 head thread.
- Tribrach: for levelling and centring, ideally interchangeable between instrument and targets.
- Total station prism: a glass prism with a known prism constant, such as 0 mm or −30 mm, which must match the instrument setting.
- Prism pole and bipod: a pole with a calibrated bubble for detail points and stakeout.
- Data collector or controller: optional on models with onboard software, essential for robotic work.
- Spare batteries and charger: most instruments run about a working day per battery.
Our guide to tripods, tribrachs and prisms explains how each accessory affects accuracy.
How to use a total station: setup and station orientation
Operating a total station follows the same sequence on almost every job: set up, orient, then measure or stake out. A careful station setup prevents the most common errors.
- Set up and level the instrument over a known point using the laser or optical plummet and the electronic level.
- Enter settings: instrument height, prism constant, temperature and pressure for atmospheric correction, and the job's coordinate system.
- Orient the station by sighting a backsight point with known coordinates. Alternatively, set up freely and use resection on two or more known points.
- Check the orientation by measuring a third known point and confirming the difference is within tolerance.
- Measure detail points with codes for features, or run the stakeout program for setting out.
- Close the job by re-measuring the backsight to confirm the instrument has not moved.
In total station construction work, such as using a total station for construction layout, the stakeout routine displays the angle to turn and distance to move until the prism reaches the design point. Total station layout of grid lines, anchor bolts and building corners routinely achieves millimetre-level results at short range.
Total station calibration and service
Total station calibration keeps systematic errors small and should combine regular field checks with periodic workshop service. Drops, transport vibration and temperature change all shift adjustments over time.
- Collimation and trunnion axis errors: checked by measuring a target on both faces; most instruments have an onboard routine to store corrections.
- Vertical index error and compensator: checked with the onboard calibration program.
- Plummet: rotate the instrument and confirm the laser or optical plummet stays on the mark.
- Tribrach and pole bubbles: often the largest source of centring error, and cheap to adjust.
- EDM check: measure a known baseline and compare.
Many firms send instruments for total station service once a year or after any impact, with field checks before critical jobs.
How much does a total station cost?
Total station price is driven by angle accuracy, reflectorless range, software platform, ingress rating and automation. Across the global market, new manual instruments typically start in the low thousands of US dollars, while robotic total stations usually cost several times more.
Total station cost also includes accessories, field software, calibration and training, which can add a noticeable share to the instrument price. Used instruments are cheaper but should come with a recent calibration certificate. These are broad market ranges, not quotes.
Mars Geosystems supplies standard, reflectorless and Android total stations with an MOQ of one unit, a one-year warranty and OEM branding from 10 units. For current pricing on a specific configuration, use our quote request page.
Frequently asked questions
How does a total station work?
A total station measures the horizontal angle, vertical angle and slope distance to a target. Electronic encoders read the angles, a compensator corrects for tilt, and an EDM measures distance using infrared or laser light. The onboard computer then turns these three values into horizontal distance, height difference and coordinates for each point.
What is a total station used for?
Total stations are used for boundary and topographic surveys, construction layout, road and rail setting-out, as-built checks, volume measurement and deformation monitoring of structures. They work well where GNSS struggles, such as near tall buildings, under tree cover, indoors and in tunnels, and wherever millimetre-level accuracy at short range is required.
What is a GPS total station?
A GPS total station usually describes using a GNSS RTK receiver and a total station together on one coordinate system. The GNSS rover handles open areas and control quickly, while the total station measures points in obstructed areas. Some workflows also use GNSS to position the total station itself before it measures surrounding detail.
Do you need a prism for a total station?
Not always. Reflectorless total stations measure directly to surfaces such as walls and pavement, typically up to several hundred metres or more depending on the model and surface. A prism is still preferred for control points, long distances and highest accuracy, because it returns a stronger signal and gives a clearly defined target.
How often should a total station be calibrated?
Most firms run quick field checks, such as two-face observations and plummet checks, weekly or before critical work, and send the instrument for a full workshop calibration about once a year. Any drop, heavy knock or unusual closure error is a reason to check calibration immediately rather than waiting for the scheduled service.
How accurate is a total station?
Survey total stations typically measure angles to 1" to 5" and distances to about 1–2 mm + 2 ppm with a prism, or a few millimetres plus ppm in reflectorless mode. At normal working ranges of up to a few hundred metres, careful users achieve positions within a few millimetres, limited mainly by setup and centring.
Need equipment for this work?
Tell us the job, the country and the quantity. An engineer replies with a configuration and price within one business day. MOQ is one unit; OEM is available.
