How to Use a Surveyor's Transit

A transit level can be used to establish property lines.

A surveyor's transit level is an instrument used to calculate the horizontal and vertical distance from one point to another. A transit level is often used during land surveying or construction planning. While the basic instructions remain the same for all transits, setup is important as incorrect preparation may cause inaccurate measurements. Doing so will allow a beginner to easily learn to use a transit and practice land surveying either as a trade or a startup profession in little time.

Instructions

1. Set the tripod that will house the transit instrument on a stable, level section of ground. This should be along an area where the measurements will be taken. Manually adjust the legs of the tripod by hand to maneuver them into a level position. Some tripods have built-in bubble levels to assist with stabilization.

2. Secure the tripod legs by locking the tripod extensions in place. Gently rock the tripod to make sure it is as stable as possible for the transit to rest on. If the transit slips off, it may become damaged.

3. Mount the transit on top of the tripod. The transit can be secured to the tripod by either locking clips or by mounting screws provided by the manufacturer. Make sure the transit is secured and bubble level shows the transit is sitting level.

4. Properly calibrate the transit. Turn the calibration screws away or toward one another. Turning the screws will cause one to become tighter while the other becomes looser. Keep turning screws until the calibration bubble is centered on top of the transit and shows proper calibration.

5. Check the accuracy of the transit. Place the measurement rod 100 feet away from the transit and tripod. This rod comes with the transit box. Make sure the rod sets vertically secured so it can be viewed through the transit. Place another rod in the opposite direction 100 feet away in the ground so it is vertically secured. The tripod should rest in the middle of the two rods.

6. Use the transit to take a reading of each rod. Record the reading given by the transit on paper. Move the transit instrument and tripod to another area along the line between the two rods and take another measurement. Again, ensure the tripod is level and secure before any measurements are taken.

7. Compare the readings. If both measurements match, the instrument is perfectly calibrated. Repeat the calibration process until the instrument reads correctly. Once calibration has been completed, the transit is ready to be used for measurements for your project.

Tips & Warnings

• If the transit cannot be calibrated after repeated attempts, take it to a professional technician.

• Make sure to line up the measuring rods each time you make new measurements.

References

• University of California Davis: Using the Transit
• Grounds Mag: Use a Transit
• Colorado State University: Surveying