Congratulations on your choice of this electronic digital theodolite with laser. Setting up traverse angles and distance of traverse legs. The initial setting operation includes fixing the theodolite on a tripod, along with approximate levelling and centering over the station mark. Unclamp one of the horizontal clamp either will do and traverse the instrument so that the plate bubble is parallel to two of the footscrews.
Magnetic compass measures the angle up to as accuracy of 30. Theodolite tribrach with circular level and optical plummet. Repairs should only be carried out by geofennel authorized workshops. Drive the tripod legs into the ground using the brackets on the sides of each leg. The theodolite is set up at some suitable place in the vicinity of the points which are to be set out hence the title free station as the choice of the instrument position is arbitrary. Crossstaff is the simplest instrument used for setting out perpendicular i. Now, and only now, place the instrument on the tripod and secure it with the central fixing screw. Levelling up the instrument after setting up the instrument, level it up approximately with the bullseye bubble. Total station setup and operation university of south alabama. Press the key in special mode, the cursor in display board moves to left. Following the measurements to be described here, this will ultimately become a known azimuth from which all further measurements taken. Press the key again, the theodolite returns to the former status. Dec 17, 2018 drive a surveyors nail into the ground at the point where you want to set up the theodolite. Slide the theodolite on the tripod head until the reference mark is centered in the optical plummet.
The temporary adjustment includes the following series of steps. If the tripod is not set properly, a great deal of time will have to spent on subsequent operations 2 to 4. As an angular instrument, the theodolite has from time to time received such improvements that it. There are variety of theodolite vernier, optic, electronic etc. Until recently, transits and theodolites were the most commonly used. The art of setting up a theodolite over a station theodolite there should be the following controls silver knobs. This is a class iiia laser tool and is manufactured. Set up the theodolite sight the initial point and read the direction e. Transit theodolite tripod and ranging rods procedure. Accurate bisection of the arrow held on the point a is done by using the lower tangent screw. The pibal theodolite uses a prism to bend the optical path by 90 degrees so the operators eye position does not change as the elevation is changed through a complete 180 degrees. Move the theodolite to b, sight a and set the horizontal circle to 258 degrees. Unlike optical levels, theodolites must be set up over.
Surveying instruments and technology theodolites routledge. Before making the first setup of the day, visually inspect the instrument for damage. Pdf how to use the theodolite for vertical and horizontal. It is a basic course for all universities for civil engineers. A theodolite or total station is set up over a control point which has known coordinates. Objectives after completing this topic you should be able to. Release the upper clamp and direct the telescope approximately towards the point p.
What is the best method of setting up a theodolite. Secure the front tripod leg and move the two other legs to centre the theodolite by using the plumb bob. The tripod legs are spread out and rested lightly on the. At this stage the theodolite is ready for reading angles and this procedure.
The theodolite is set up at the site under investigation, levelled and a marker pin placed on the ground to mark the station. Loosen the upper plate, set the vernier to read zero and clamp the upper clamp. Theodolite surveying for nondestructive biomass sampling. Extend the legs of the tripod as far as is required and. My station station height the exact height from the mean sea level to the platform or site where you set up your theodolite. The theodolite helps us a good within the engineering field. Coordinate and then select ok and return to backsight. The number of gratings involved in a measurement is determined from wholecircle electronic scanning. With the theodolite set up at s, sight t and set the horizontal circle to read zero along this direction. Press it in special functional mode to move cursor moves up or. Dennison how to set up a theodolite a a theodolite is always set up over a point. Introduction theodolite is used to measure the horizontal and vertical angles.
Locate your desired reference point that you wish to set up above. Setting up a theodolite with either an optical plummet or laser plummet can be quickly achieved in a few easy steps. Sources of error in theodolite work theodolite surveying. The use of high speed computers for converting angle measurements to point locations allows theodolite surveying techniques to be used for describing the physical structure of vegetation assemblages in considerable detail with relative ease. Here in we have gathered some pdf lectures on surveying. Before measuring these angles, temporary and permanent adjustment of theodolite have to be done at the initial stage. Ch1 ch2 ch3 ch4 ch5 ch6 ch7 ch8 ch9 ch10 ch11 ch12 ch ch14 problem. At the end of this course, a student should be able to appreciate the role of thesurveyor in.
Theodolite is used for measuring horizontal, vertical and deflection angles. You do not have to fill out the other fields for a rem measurement, however, it is good practice to measure and enter the instrument. Set up, centre and level the theodolite over the ground point b. These instruments have glass circles that are graduated into unnumbered gratings. The theodolite is typically mounted on a rugged steel stand, set up so it is level and pointed north, with the altitude and azimuth scales reading zero degrees. How to set up a theodolite above a known point lssltd. Measure the height between the ground and the instrument. However a vernier theodolite measures the angles up to and accuracy of 10, 20.
This distance is called stationing and it is measured by a tape. Make sure you use the metric side of the tape measure if working with metric units. Press it under shift mode to export current angle to serialport and to record with electronic controller. Press this key twice, the horizontal angle is set to 0. Surveying instruments operators manual dt240 dt540 dt740 dt940 dt540l dt740l dt940l digital theodolite class 2 laser product. Loosen the lower plate and swing the telescope until the left point a is sighted. For calculation of independent rectangular coordinate from the field observations, the following computations make in their order of sequence. Check the machined surfaces and the polished faces of the lenses and mirrors. Mark the point at which the theodolite will be set up with a surveyors nail or a stake.
Theodolite survey application in height and distance measurements. Set up the instrument over o and level it accurately. Whenever a particular direction and horizontal distance is to be entered for the purpose of locating the point on the ground using a target, then the instrument displays the angle through which the theodolite has. Set the vernier a to the zero of the horizontal circle. If a conventional theodolite is being used it normal to turn the instrument to north and reset the horizontal angle to zero. The theodolite is an instrument used in precise surveying to locate points in space by triangulation. This instrument plays a major role in measurement horizontal angles, vertical angles, bearing, etc. The plate vial is adjusted correctly and the instrument. The first step of the temporary adjustment is the setting up of the theodolite. Set the theodolite at a and align zero on the circle with north. Unlock the compass and rotate the theodolite base so that the compass shows that the theodolite is pointed very close to towards true north. Plumb bob method i setting up the tripod this is the most important operation. Station parameter description example station name a unique textual andor numeric identifier to that station. Turn the instrument and direct the telescope towards a to bisect it accurately with the use of tangent screw.
This document outlines the procedure for using the theodolite to measure angles. Automatic index which improves and speeds up vertical angle measurement and provides a red warning screen circle clamp for setting zero, repetition, or carrying bearings. This is most often a survey marker or a hilti nail or a pk nail. Do not remove warning labels or safety instructions. Press it under shift mode to make tracking measure once per second and precision is 0. Once the theodolite has been levelled, it is necessary to select a reference object ro. With the help of upper clamp and tangent screw, set 0.
Engineering surveying 221 be setting out and site control. Further, different methods of curve setting have been emphasized. The compass was moved onto the standard and it became demountable. The right angle is set out by a theodolite at point a. Set up the tripod legs, taking care to set the height where the instrument sight will be at a comfortable eye level. So far, weve seen how to set up the theodolite, weve also seen how to get it ready for use. Thank you for selecting this series of digit theodolite. Theodolite setting up the theodolite the sequence of operations required to prepare the instrument for. Look through the optical plummet again and adjust the theodolite foot screws for ne alignment with the reference mark. Theodolites how does a theodolite work theodolite vs. Chapter 3 surveying equipment, measurements and errors. Field book example please remember that you can use additional pages to clearly show all necessary information trial 20m 40m 60m 1 30 58 90 2 30 57 89 3 31 57 90 avg. The separate microscopes were replaced with the common one, and its ocular was set next to the telescope ocu lar.
Set up the theodolite at station point o and level it accurately. The regular movie mode is similar to the photo mode in theodolite, recording a basic video with options to show an overlay with crosshairs, geodata, and a custom note. Any angular resection is carried out to fix the position of the free station point. This document pdf may be used for research, teaching and private study purposes. We hope students all over the world will find it helpful. Theodolite in surveying types of theodolite parts of. Make sure the height of the tripod allows the instrument the theodolite to be eyelevel. Support centring screw it with one hand and insert and tighten the. How to set up a theodolite over a point hitechniques. Mount the instrument mont the instrument onto the tripod carefully, and fix it with the 5 retaing bolt of the tripod. Mount the theodolite by placing it atop the tripod, and screw it in place with the mounting knob. Location and description of major components figure 11 illustrates the major components and general features of the theodolite.
Theodolites are capable of greater precision and accuracy. Set the target height to the measured height of the mirror target. The study consists of principles of survey, theodolite survey, tacheometric survey, setting out works and total station survey. Then im going to set the instrument up at 90 degrees and were going to measure a vertical angle to the corner of the roof. Instead of the compass, a tubular level was set up between the standards.
Theodolite horizontal circle reading is 78 degrees wcb. Theodolite parts and its functions for measurements in surveying. Jul 14, 2020 set the tripod over the survey point with the head level and legs making about a 70degree angle with the ground. The instrument is then pointed at another control point in order to orientate the instrument to north. Repeat this procedure for each 90 revolution of the instrument until the. Angles will be measured from this point, as will distances. For setting up the instrument, the tripod is placed over the station with its legs widely spread so that the centre of the tripod head lies above the station point and its head approximately level by eye estimation. The simplest type consists two parts 1 the head 2 the leg. These are important in order to eliminate errors in surveying. The temporary adjustment of the theodolite mainly includes a set of operations that are carried out to make it ready for taking the observations.
Surveying is a very important part of civil engineering. Support centring screw it with one hand and insert and. These adjustments of theodolite have to be done to measure the correct angles. It is important that this point has a defined centre. Adjust the vials first adjust ciruclar vial, then adjust plate vial. Set up the theodolite on the tripod at the distance of 2. The use of the theodolite in detail surveys is covered in later topics.
Select coord and then enter the backsight target coordinates nbs, ebs, zbs and select ok sight in the target and inspect the azmth it should be reasonable for your coordinate system. How to use a digital theodolite part 1 of 2 youtube. The theodolite is used to measure horizontal and vertical angles. This point is the basis for measuring angles and distances. Permanent adjustment of transit theodolite, methods of repetitions and reiterations. Pdf the function of a theodolite is to measure angles in. Minor survey instruments boxsextant, planimeter, pantagraph, their working. Extend the legs of the tripod as far as is required and tighten the screws firmly. Write up the lab in your field book, refer to the following example. To use theodolite, it is necessary to know about theodolite parts, types of theodolite, and for what it is used wisely in the field. Here the following topics of surveying are discussed. Set tripod and instrument with optical plumb almost over the station.
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