Construction tools for performing measuring operations have undergone significant changes in recent years. Traditional levels and slats are fading into the background, giving way to more functional and technologically advanced electronic analogues. Optical and laser instruments for determining the position of construction objects provide high-precision results, while also performing complex mathematical calculations based on the data obtained. And it is quite logical that as the devices become more complex, questions arise about how to work with the level? Educational program for beginners, presented below, will allow you to master the basic rules for using such devices. Despite their physical ergonomics, the process of operation involves performing a number of procedures, on which the correctness of the result will depend.
Device of optical levels
The basis of the device is formed by a tribrach - this is a metal circle, the position of which is fixed by three supports with regulatory elements. Lifting screws allow the structure to be optimally positioned on the site, minimizing the risk of deviations. The device also includes a horizontal dial, a telescope, cylindrical levels and a compensator in the form of a magnetic or air damper. with a level of this type? Initially, the adjustment is made using the above-mentioned screws, and the measurement itself is carried out through a telescope. Depending on the configuration, optical devices may have several lenses in a set that allow measurements to be taken under different conditions. To correct the clarity of the device, the head part with optics also includes adjusting screws, which reduce the risk of a large error. Using such equipment, you can determine the height of the structure, differences in the position of individual objects, fix angles of inclination, etc.
Laser level device
Models of this kind do not include a telescope, which saves the user from independently determining the geometric parameters of the object. The working basis is a laser emitter that projects a beam onto the target area. The design also provides for the presence of control fittings, but in this case the margin of error is eliminated, since most models, regardless of position, can automatically adjust the beam direction angle relative to the horizontal.
How does a laser level work? The device prepared for the operation is oriented with optics towards the object, as a result of which a point is reflected on the surface, by which the height can be estimated and measurements can be taken. Such equipment is good because it reduces the risk of error due to the human factor. Its advantages also include a wide range of additional options related to the processing of received information.
Features of rotary models
These are the most technologically advanced devices designed for marking on a construction site. The key feature of such models is the presence of a rotating detector, which contains two lasers. They can move at speeds of about 600 rpm, projecting a beam over a 360° range. How to work with a rotary type level? The technique for handling such devices generally corresponds to standard laser devices, and the difference lies only in the organization of the final markings. That is, if the beam in conventional models provides information about one characteristic, after which it needs to be moved, then the rotary technique allows complex calculations to be carried out from one position. This approach is especially effective when installing windows, performing surface finishing, and in other operations where it is necessary to obtain data about the position of different objects within the same room or construction site. But in open areas there may be restrictions associated with reaching the target object.
Before you begin the main work activities, you should consider measures to ensure the safety of the device. First of all, the case must be protected from water, dirt, dust and physical shock. As a rule, the design of construction levels has multi-level dust and waterproof insulation, but this may not be enough. For example, even models with a protection class higher than IP54 cannot be used in heavy rain without an additional shell. The same applies to the threat of direct sunlight. Temporary overheating of the equipment may not damage it, but it will certainly affect the accuracy of the measurements.
How to work with a level if it is frosty or hot outside and surface cover will not help? Initially, you should make sure that the device is, in principle, suitable for operation at a particular temperature condition. As a rule, models from major manufacturers can be used in the average range of -10 to 25 °C. But even in this case, it is necessary to adhere to certain operating rules. For example, optical models are sensitive to temperature changes. After taking the measurement, the device should be brought into a warm room and warmed up in the supplied case for 30 minutes.
What will you need for the job?
A tripod should be used to ensure the correct position of the device. You can do without it in a room with a flat base, but if it comes to working on a construction site on bare ground, then adjustable equipment will not be superfluous. But even indoors without special load-bearing devices will be inconvenient to work with the device. For such purposes, ergonomic holders are provided. They can be attached to walls, floor coverings and even to the ceiling.
A special rail will also be required. Its scale will allow you to mark divisions on the target surface, along which the required readings will be recorded. How to work with a level and staff? Traditional methods assume that two people will be involved in the process - one is directly responsible for recording the data, and the second holds the staff. However, the latest models of laser electronic devices automatically process the data, taking into account special bar codes of the strips. In this case, the user only needs to activate the corresponding function and set the scale position correctly.
Operation of optical instruments
As already mentioned, work begins with setting up the telescope. The main task at this stage is to achieve extreme clarity of the image of the object. Adjustment is made using screws, and correctness is assessed by looking through the eyepiece.
Further work, unlike laser models, is carried out by two people. One worker sets the staff perpendicular to the ground, and the second takes readings using the image of an optical level. How to work with it so that the correctness of the data does not decrease during the operation? Firstly, much will depend on the reliability of the position of the device. Therefore, special attention is initially paid to the stability of fixation of the legs. Secondly, professional surveyors use spirit levels. These are devices with bubble levels, thanks to which both the position of the tripod and the position of the level are adjusted. When the device is ready for use, the pipe sight is aimed at the divisions of the staff. Then all that remains is to record the readings in the technical journal.
How to work with a laser type level?
The device is also fixed using a tripod or special holders. Once you have ensured that the installation is secure, you can begin working activities. After pressing a special button, a beam is sent to the target surface. Lines can be projected horizontally or vertically, and some models also provide the possibility of cross-radiation. After this, the device automatically takes readings from the prepared staff with divisions. If you plan to mark over long distances, then you cannot do without a special receiver that will separately record the position of the beam. a level supplemented with such a device? Basic operations are also taken over by automation. The operator only needs to monitor the readings on the display of the receiver, which can record the position of points at distances of about 80-100 m. At the moment of registration of the beam, the device will give a corresponding signal and display the received information on the screen, which is recorded in the log.
Instrument Maintenance
Optical devices require the most maintenance. Therefore, after each use, it is necessary to wipe the eyepieces, lenses and surfaces of the telescope. The slightest contamination can affect the accuracy of the data reflection. For example, the Control company has a wide range of devices of this type, and also recommends regular verification. In reviews of this product, there is often criticism that notes that clarity does not work on the Sokia level. The reasons for the decrease in image quality of models in this series may include dust in the optics and structural defects. For example, if the same lenses were not installed tightly. In this case, verification procedures should be carried out using a white sheet of paper. It is located at a predetermined distance near the marking strip. Correction of the optical equipment is carried out until the measurement results coincide with the previously known actual data.
A level is a device used to carry out geodetic measurements. It is used in the construction of buildings, roads, technical structures and other objects. Its main purpose is to measure the difference in height level between areas/levels of a construction site. For example, it is used to measure the difference between the height of the sides of foundations, reinforcing belts of buildings and other structural elements, the arrangement of which requires increased accuracy. Before use, preparation of the device is required - bringing its individual working units into working position.
Tripod setup
To achieve the best results when taking measurements using a level, you need to learn how to use this device. Working with it begins with installing a tripod. The main criteria that determine the standards for the working position of a tripod are:
- vertical level;
- horizontal level;
- sustainability.
The presence of a vertical level in the position of the tripod on the ground allows you to reduce the error in the final measurement result. This error may result in a violation of the horizontal level. Thus, the vertical level of the tripod affects the display of the horizontal level in the eyepiece of the level.
The horizontal level of the tripod is determined by the slope of the upper landing platform. The presence of a deviation of its surface from the horizon by an angle whose value exceeds the permissible value can lead to a change in the vertical level displayed in the eyepiece of the device.
The stability of the tripod position is of paramount importance. Depending on the condition of the surface on which the tripod is placed, measures must be taken to ensure its stability. As part of these measures, the soil or other surface is checked for looseness, holes, cracks or other imperfections. It is necessary to check the stability of each tripod support: none of them should fall into the ground, move to the side, or otherwise change their position.
When determining the degree of stability, it is important to take into account additional loads: during measurements, the level will rotate on the landing site. The forces applied to rotate it should not move the tripod from its position.
Knowledge of its structure will help you install the tripod correctly. It consists of the following elements:
- landing site;
- adjusting screws;
- support legs (3 pcs.);
- clamps;
- support tips.
The landing pad is a plane located at the top of the tripod. It is equipped with grooves with threaded connections, various clamps and adjustment screws. There is a rotating mechanism underneath it, which allows you to rotate the level without shifting the level of its position. This platform connects the tripod supports.
The adjustment screws work in conjunction with the platform and other parts of the tripod. With their help, you can change the position of the landing plane in space. They allow you to achieve the correct level of its location - its parallelism to the horizon. Some of the adjustment screws are used to fix the position. They are used after the site adjustment is completed. Their presence makes it possible to limit its spontaneous movement and eliminate deviation from the horizon.
The support legs of a tripod are the main elements of its design. They are fixed in one area - under the landing pad, and radiate to the side in rays. Their lateral reach is limited by the fastening mechanism and the straps connecting their middle parts. Each of the legs is telescopic. Extension and fixation of the position of the support knees is carried out thanks to clamps.
Clamps are simple mechanisms located at the articulation points of the knees of the legs. They operate on a lever principle, which allows you to loosen or lock the clamp with one movement. This solution for this tripod design unit is optimal, since the screw clamps that were used in earlier modifications required more time and effort to use.
The presence of telescopic supports and lever clamps on them allows you to increase the efficiency of tripod installation even on rough terrain. If necessary, one or more supports can be extended only partly, and the remaining ones can be extended to their full length.
The tripod support tips are pointed metal ends equipped with a small “hilt” that prevents the tip from penetrating deep into the soil. The presence of these tips with a limiter increases the static nature of the design. On a smooth surface, the pointed ends prevent the support legs from sliding, which prevents the level from moving.
On soft and loose surfaces, the tips sink into the soil, but the limiter prevents this sinking by controlling its depth. This allows you to avoid accidental subsidence of one or more supports at the same time. Often the tips are equipped with “claws” that are used to press them with the sole of the foot. Thus, the tips are pressed by the operator of the device into the soil to the required depth.
Setting up the level
The level is an optical device. For its proper operation, its position in space is important. To adjust it, special mechanisms are provided. In construction, levels with built-in bubble levels are most often used, adjustment with orientation to which allows you to achieve the correct location.
For the most effective adjustment, the level is equipped with three screws that change the position of the device along three axes: X, Y and Z. By rotating these screws one by one, you can achieve the correct position. When carrying out adjustment manipulations, it is important to pay attention to the position of air bubbles in flasks with liquid. For best results they should be located between the boundary lines.
There is a circular bubble level at the top of the device. There are two circles marked on its flask: large and small. After leveling the level, the bubble should be located strictly in the center of the small circle. This procedure is the most difficult step in setting up the level. To facilitate its implementation, you need to install the tripod as “level” as possible, since the free adjustment of the device using three screws is limited. The next step in setting up the level is to adjust its optical lens.
Focusing
Performing focusing manipulations is ensured by the presence of several adjustment elements on the device:
- eyepiece rings;
- focusing screw;
- guide screw.
The eyepiece ring is used to focus the eye on the reticle. The grid of threads is the marking that the eye sees through the eyepiece of the level. It consists of a vertical line and several horizontal ones. Measurements are taken along the longest horizontal line. Its intersection with the vertical stripe is the starting point for measurements, which makes it possible to avoid setting the horizon when carrying out calculations of average significance.
The focusing screw is a focus regulator; it is used to adjust the focus on the measurement object itself. Any level is used in conjunction with a measuring rod, which makes it this object. After a clear image of the reticle appears in the eyepiece tube, it is necessary to turn the focusing screw until the image of the staff located behind the reticle becomes clear. When the focus control is rotated, the lens moves inside the eyepiece tube, which helps to zoom in or out of the image. Focus correction must be performed before each data acquisition.
The aiming screw rotates the level around its axis, allowing its lens to be moved to the desired position. In this position, the vertical marking line should be in the center of the measuring rod.
To increase the accuracy of the results, you need to know how to correctly take instrument readings, what they mean and how to correct the result based on them.
Measuring and recording values
Measurement through a level is made by selecting a reference point and subsequent correction of the position values of other points based on data about the starting point. Example: The measuring rod is installed at the highest point of the plane being measured. Then the level is aimed at the staff scale.
To make it easier to take readings, the staff moves up or down so that the crosshairs of the lines in the lens align with the whole number indicated on the staff scale. This value is fixed. After this, the staff is transferred to another measuring point. In the new position, it is necessary to find the fixed value on the scale - it must also coincide with the crosshair of the lens. After combining these indicators, the bottom edge of the staff will become the point at which the mark will be set.
In most cases, such marks are placed on benchmarks - special structures between which construction cords are stretched (used, for example, when pouring foundations or laying brick walls). Depending on the alignment of the level crosshairs and the value of the staff scale, it may be necessary to move the reference point or shift it along the vertical axis. Ultimately, all key points are marked along the lower edge of the staff and coincide with the first reference point according to the level indicators.
The level allows you to set measuring points to the same level over large areas, which is impossible to do using any other measuring instruments. The distance that can limit the action of the device is determined by its technical capabilities and the characteristics of the lens. Besides, the measurement process can be disrupted by incorrectly selected tripod installation height. If the permissible height of the position is exceeded, and measurements must be taken in a low place, the length of the measuring rod may not be sufficient. This will lead to the fact that there will be no ruler in the lens of the level - it will be impossible to take measurements.
A level is a device for determining height differences, checking the evenness of a surface by determining the excess of one point over another with a horizontal beam. Levels are divided into optical, digital and laser.
How to use an optical level?
An optical level kit consists of a tripod, a staff with divisions in millimeters on one side and centimeters on the other, as well as the level itself.
- 1 step. First you need to choose a place to install the level. The most convenient location is considered to be in the center of the measured area. A tripod is installed at the selected location. To achieve a level horizontal position, it is necessary to loosen the clamps of the tripod legs, set the tripod platform (head) to the required height and tighten the screws.
- Step 2. The level is installed and secured with a screw on a tripod. By rotating the leveling screws, using a level, the horizontal position of the device is achieved.
- Step 3. All that remains is to focus. To do this, the telescope must be aimed at the staff and rotating the focusing screw to obtain the sharpest image possible; the eyepiece ring adjusts the focusing of the reticle. If it is necessary to measure the distance from one point to another or to remove the axes of a building, then centering is carried out. To do this, the level is installed above the point, and a plumb line is suspended from the deadbolt. The level is moved along the head of the tripod, while the plumb line must be above the point, then the device is fixed.
- Step 4 After installing and configuring the device, you can proceed to research. The leveling rod is installed at the starting point (or altitude reference point), and a reading is taken along the middle thread of the leveling thread grid. The count is recorded in the field journal. Next, the staff is transferred to the point being measured, and the procedure for taking and recording the reading is repeated. The difference between the readings of the initial and measured points will constitute the excess.
How to use a laser level?
Before starting work, you must check the operation of the device. To do this, you need to charge the battery or insert batteries and turn on the level. If the beam shines brightly and clearly, then the device is ready for use.
To achieve high quality markings, the following rules for positioning the device must be observed:
- The projection of a line or plane must occur continuously. There should be no obstacles in the path of the beam.
- The distance from the level to the object should not exceed the maximum allowable for the selected model. As the distance increases, the marking error increases. But the use of a special receiver allows you to increase the range of use of the device up to 2 times.
- The laser beam is dangerous to the eyes of animals and people, so before carrying out work it is necessary to warn others and, if possible, isolate animals from the work site.
Setting up a laser level depends on the selected model; it is important to remember that disabling unused functions allows you to save battery power and increase the operating time of the device. Basic settings:
- To achieve an accurate result, the device must be placed on a flat surface using a tripod, and the level must be in a stable position. Some models are designed to be mounted to the ceiling or wall; in this case, it is important to prevent the device from moving or shaking.
- Before starting work, it is necessary to level the device horizontally by rotating the screws. Many modern models have a self-leveling function. Such devices do not allow the device to be positioned incorrectly and sound an alarm when an error occurs.
- Depending on the task, you need to adjust the visibility of the vertical and horizontal axis. In some models, it is also possible to select the “line” or “dot” mode and adjust them.
- In rotary levels, you can adjust the beam rotation speed or angle to set the working sector.
- If it is necessary to measure over long distances, you should use a laser beam receiver, which must be mounted on a staff and placed on the point to be measured.
Using a laser level in construction or repair allows you to perform a large number of tasks. Methods of use depend on the specific goals set, for example:
Using a laser level when working on the floor:
- To determine the evenness of poured concrete. To do this, the rail must be placed against the wall anywhere in the room and marked where the red beam is located on it. After this, take several more such measurements at different points in the room and compare the deviations of the indicators.
- For decorative laying of floor tiles. To do this, you need to tilt the device and transfer the beam to the floor, while fixing the level. The most popular method is when the rays intersect at right angles, which allows you to carefully lay out the tiles. The presence of clamps included in the laser level allows you to project a perpendicular intersection onto any surface.
Using a laser level for wall work:
- To level the walls To do this, you need to direct the beam along the surface and measure the deviations.
- Sticking ceramic tiles and wallpaper The use of marking walls with a laser level allows you to lay out tiles or paste wallpaper quickly and perfectly evenly. Either one vertical beam is used for wallpaper or the intersection of two beams for tiles. To save power, usually only the first row is glued along the rays, the rest are aligned along the first, sometimes performing a control alignment with a level.
- Installation of equipment, cornices, shelves and other household uses of the level. Laser levels have replaced pencils, tape measures and bubble levels. Projecting rays onto the wall allows you to quickly and without hassle deal with a large number of everyday issues.
In conclusion
The level is an indispensable device both at construction sites and in everyday life. You can buy a laser or optical level in our online store. We also provide training on the use of professional geodetic and construction equipment. Contact our specialists and we will answer all your questions.
N
ivelir at a construction site, the second most important tool after a measuring tape. Having no idea how to work as a leveler, there is no point in even thinking about starting any more or less serious construction. At the same time, the operating principle of the level and the basic techniques for working with it are so simple that even a primary school student can master them.
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Video version of the article
Level device
Let's look at what a regular optical level consists of and how it works. The main part of the device is an optical tube with a lens system capable of zooming in on observed objects with a magnification of twenty times or more.
The pipe is mounted on a special rotating frame, necessary for the following functions:
- tripod mounts;
- setting the optical axis of the level to a strictly horizontal position, for which the frame has three height-adjustable “legs” and one or two (in models without automatic adjustment) bubble levels;
- precise horizontal aiming, which is carried out with paired or single handwheels.
In some models, the bed has a special dial, a scale that allows you to measure or construct horizontal angles.
On the right side of the pipe there is a handwheel designed to adjust image sharpness.
Adjustment to the operator's vision is made by rotating the adjustment ring on the eyepiece.
When looking through the eyepiece of a level telescope, we will see that in addition to bringing the object observed through the device closer, the level superimposes a system of thin lines on its image, called a reticle or reticle. It forms a cross-shaped pattern of vertical and horizontal lines (see Figure 1).
Additional devices and equipment
In addition to the device itself, for work we will need the already mentioned tripod, as well as a special measuring rod with divisions and numbers printed on it. The divisions are stripes of alternating black or red stripes 10 mm wide.
The numbers on the rod are marked in increments of ten cm, and the value from zero to the end of the rod is in decimeters, with the numbers expressed in two digits. So, 50 cm is indicated as 05, the number 09 indicates 90 cm, the number 12 indicates 120 cm, etc.
For convenience, the five centimeter marks of each decimeter are also united by a vertical strip, so that the entire strip is marked with signs in the form of the letter “E”, straight and mirrored.
The optical level is considered by many to be archaic, while it is one of the most accurate instruments in geodetic research. In our review, we will satisfy the interest of ordinary people regarding the use of a level for the geometric method of constructing planes.
Two surveyors on different edges of the abyss:
Leveler (shouting): Move over!
Reika: Whaaat?
Leveler (even louder): Move over!!!
Reika: I can’t hear!!!
Leveler (mumbling): Deaf idiot...
Reika (shouting): You're an idiot!!!
The essence and specifics of leveling
There are many ways to determine the curvature of the earth's surface: by the slightest difference in atmospheric pressure, using a theodolite or water level and other devices. However, geometric leveling is considered the most universal, fast and accurate method: even with technical levels used in construction, the measurement error is only 10 mm per km.
The essence of leveling is to determine the difference in height (excess) of each of a set of points on the ground relative to a certain reference point, called a benchmark in construction. After the virtual plane has been determined, a zero mark is measured relative to it, which in most cases lies at the floor level of the first floor of the building.
In principle, there is nothing complicated in leveling except for two specific points. On the one hand, the surveyor and his partner must be able to use a level and a staff, know the intricacies of adjustment and correctly install control posts. Another nuance is that there may be objects on the ground that prevent visual contact between the level and the staff. Therefore, the installation site of the level has to be periodically moved, determining temporary benchmarks and establishing the height difference for them. But in the end, all calculations come down to banal arithmetic.
Definition of benchmark and key points
During a geodetic study of a construction site, the benchmark is placed at the lowest point of the plane, which is determined visually or by a quick “shoot through”. At this point, a massive pole with a straight cut is driven into the ground, on which it is convenient to install a rail.
The number and location of key points depends on the leveling tasks. If we are talking about preparing a foundation pit, the points are placed on the internal and external corners along the contour of the future structure. When placing control points, high precision is not required; it is only important that there are no local bumps or holes in the place where the stakes are installed.
Within the boundaries of a populated area there are special, measured and officially approved reference points for reference to them when measuring new construction sites.
All points should be as equidistant as possible from the level installation site and be at least 5 meters away from it. If you are leveling a small area, you can use a level to shoot all the points from the side, or use a hydrostatic level.
Installation and alignment of the visor
First you need to set up a tripod. Having loosened the screws securing the telescopic legs, the tripod needs to be aligned so that the upper platform lies in a horizontal plane; here everything is done “by eye”. The legs need to be pressed into the loose soil, pressing the foot against the stop, and the distance between them should be the same. The height of the legs must be adjusted so that the tripod platform is at chest level, and then tighten the screws.
When the tripod is installed, the level itself is attached to it using a central screw. It has two platforms: the lower one is fixed to the tripod with a screw or other standard method, the upper one rests on three adjusting screws. On the sides of the triangle formed by the screws there are three cylindrical pre-setting bubble levels. By rotating one pair of screws, you first need to ensure that the bubble between them is exactly between the marks. After this, by tightening the third screw, two other levels are set. The fine adjustment indicator - a round level - is located on the body of the level's optical tube. It may be necessary to turn the adjustment screws a little to ensure that the bubble is positioned exactly within the circle mark. The level is ready for use.
Leveling rod designations
Before you start shooting terrain, it's a good idea to figure out how to navigate the staff. Really, what are these incomprehensible letters “E”, what are these black and red marks? It's actually very simple.
The rail is divided into segments, each 10 cm long. Inside each segment there are black and white sections, each 1 cm long. The outer three black sections are united by a side line - this is to make it easier to visually determine the center of the segment. The numbers indicate in which ten centimeters the segment marks are located, that is, essentially the position on the rail is determined by the number of white and black sections added to the ten number.
But accuracy of one centimeter is clearly not enough. The fact is that on the back side of the staff there is a regular millimeter graduation, which is not very convenient to use over long distances. Therefore, the assistant holding the staff can further adjust the slider, guided by the surveyor’s commands “above” and “below”, and then show the number of millimeters on his fingers. Also, some levels are equipped with a metric grid, which makes it even easier to determine this deviation.
Finally, the most interesting question: why the top of the rail has red markings located in the reverse order. The fact is that the old levels did not have an additional lens and the surveyor saw the image upside down. But you are unlikely to have to deal with such “dinosaurs”.
Procedure for measuring point elevation
Before shooting a point, an assistant should set the staff as close as possible to the control peg, gently resting it on the adjacent ground. During measurements, the rod must be held motionless and strictly vertical, using a plumb line or a round bubble level for alignment.
The level must be turned towards the staff so that the vertical axis of the grid is located exactly in its center. After this, by rotating the optical screw, you need to adjust the sharpness of the image so that the marks on the staff are clearly visible. Then you need to adjust the sharpness of the reticle display by rotating the ring on the eyepiece.
To determine the excess, you need to note the number of the segment on which the vertical axis is located, and then count how many whole black and white spaces there are from the beginning of the segment to the axis. By adding this value after the segment number, you will get the elevation in centimeters. If higher accuracy is needed, a comma is placed after the elevation, then the assistant moves the slider so that its edge exactly coincides with the horizontal axis and transmits the number of additional millimeters, which is written after the decimal point.
You can do without the slider. If the horizontal axis is located exactly in the middle of the white or black mark, add three millimeters, if in the lower quarter - one or two, if in the upper quarter - four. This visual definition is more than enough for construction.
Logging and calculations
The leveling process involves keeping a large number of records. The surveyor should have at hand a site plan, which schematically shows the object for the construction of which leveling is being carried out, as well as the location of the control stakes. Each peg must be numbered and these designations must be placed in a separate table in which the measured excesses are noted.
Now about the excesses themselves. They can be relative and absolute, that is, from the level measurement plane and from the benchmark. For example, the excess of the reference point was 145.2 cm, and the reference point - 151 cm. Subtracting the excess of the point from the excess of the reference point, we find that the absolute excess will be -4.8 cm, while the minus sign makes it clear that the current is located below. Similar calculations should be carried out for each of the points.
The practical meaning of leveling is to apply marks on the stakes that are in the same horizontal plane. To do this, you need to find the highest point with the largest positive value of the elevation and add to it, for example, 20 cm. Following from one peg to another, using a tape measure, mark the value of the elevation of the point on them, to which the offset value is added - those same 20 cm. The resulting marks are used when excavating and determining the depth of the pit, or for pulling the mooring cord.
