How to use electronic level and its steps

Level is a tool often used on construction sites. Its main function is to measure elevation. How to use it correctly and quickly is an indispensable skill that every constructor must master. Let us learn how to operate it together!

Electronic reading method The current electronic level adopts three automatic electronic reading methods that differ greatly in principle:
1) Correlation method (Leica NA3002/3003);

2) Geometric method (Zeiss DiNi10/20);

3) Phase method (Topcon DL101C/102C);

Advantages Compared with traditional instruments, it has the following characteristics:
1) The reading is objective. There are no errors, mis-recording problems, and no man-made reading errors.

2) High precision. The line-of-sight and line-of-sight readings are all obtained by averaging a large number of bar code reticle images after processing, thus weakening the influence of scale reticle errors. Most instruments have the function of averaging multiple readings, which can weaken the influence of external conditions. Unskilled workers can also perform high-precision measurements.

3) Fast speed. Because it saves the time of reporting, recording, on-site calculation, and the number of retests caused by human error, the measurement time can be saved by about 1/3 compared with traditional instruments.

4) High efficiency. Only need to adjust the focus and press the key can read automatically, reducing the labor intensity. The sight distance can also be automatically recorded, checked, processed and input into the computer for post-processing, which can be integrated inside and outside the real line.

How to use the electronic level and its steps

How to use the electronic level
1) Placement of equipment: The placement of the electronic level is the same as that of the optical level.

2) Leveling: Rotate the foot screw to center the bubble in the circular level box.

3) Input station parameters: input station elevation.

4) Observation: Align the telescope with the striped level and press the measurement button on the instrument.

5) Reading: Read the height difference and height directly from the display window. In addition, other data such as distance can also be obtained.

Southern Electronic Level DL301 is operated by keyboard and measurement keys installed on the side. Displayed to the user by the LCD display, and display the measurement results and the status of the system.

During 　　 observation, after the electronic level manually completes the placement, rough leveling, and aiming at the target (bar code level ruler), the measurement result is displayed for about 3 to 4 seconds after pressing the measurement key. The measurement results can be stored in the electronic level or stored in the internal recorder through the cable connection.

In addition, if the bar code of the leveling ruler is partially occluded by less than 30% during the observation, the observation can still be performed.

Each key function description
How to use the electronic level and its steps

The erection of a tripod
The E-shaped aluminum tripod or wide frame tripod, or the ball-head aluminum tripod should be used.

(1) Stretch the three legs of the tripod to a suitable length, and tighten the fixing nuts in the middle of the legs.

(2) Tighten the hex nut on the tripod head so that the tripod legs are not too loose. Place the tripod on a given point and open the tripod so that the distance between the legs is about one meter or the opening angle of the tripod can ensure the stability of the tripod. First fix one foot, and then move the other two feet to make the level roughly level. Extend the length of the tripod legs.

(3) Step the tripod leg into the ground to fix it on the ground.

Mount the instrument on the tripod head
Carefully take out the instrument from the instrument case and place it on the tripod head

(1) Align the center screw of the tripod with the center on the base of the instrument, and then tighten the center screw on the tripod until the instrument is fixed on the head of the three frame.

(2) If you need to use a horizontal dial to measure the angle or set a line, you must use a plumb bob to center the instrument.

(3) Use three leg screws to center the bubble of the circular level, that is, level the instrument. If you use a ball-head tripod, you should lightly open the center screw of the tripod first, and then rotate the instrument around the top of the tripod head to make the circular level bubble. Center, when the bubble is in the circle, you can tighten the fixing nut on the tripod.

Place the instrument on a given point (centering)
When the instrument is used for angle measurement or alignment, the instrument must be placed on a given point with a plumb bob.

(1) Hang the plumb hook on the spiral plumb bob in the center of the tripod.

(2) Then hang the plumb bob line on the plumb bob, use the sliding device to adjust the length of the line so that the plumb bob is at a suitable height.

(3) If the instrument is not aligned with a given point, the instrument can be moved to that point without changing the relationship between the tripod legs and the head. First, place the tripod roughly on a given point, make the plumb ball deviate from this point within 1cm, hold the two legs of the tripod, adjust relative to the third leg, make the head level and height appropriate, and open the legs. Suitable to reach the ground.

(4) While observing the plumb bob and the frame head, step each frame leg into the ground.

(5) Slightly loosen the center screw of the tripod, move the instrument gently on the head of the frame so that the plumb ball is aligned with the given point, and then tighten the center screw of the tripod.

leveling instrument
Rotate the two leg spirals far away from the circular level so that the bubble of the circular level is located on the vertical line connecting the centers of the two leg spirals.

Then rotate the third screw to center the bubble. If the bubble is still not strictly centered, repeat the above operation from the beginning. Note: Do not touch the telescope during the leveling process.

adjust the eyepiece
Before the measurement operation, the eyepiece of the telescope must be adjusted according to the operator’s eyesight

(1) Rotate the eyepiece adjusting ring counterclockwise, at this time the crosshairs may become blurred.

(2) Slowly rotate the eyepiece ring clockwise until the crosshairs are clearly visible.

Sight and focus
(1) Align the telescope with the ruler, observe the coarse sight on the handle, and align the vertex of the triangle mark with the ruler (as shown in the picture)

How to use the electronic level and its steps

(2) Rotate the focusing screw in any direction until you can see the ruler clearly.

(3) Sight the ruler with a horizontal micro-motion spiral, see "Focus and Sight of the Ruler" for details

Note: Once the level has been focused and aimed at the ruler, you can move your eyes to the left and right while observing through the telescope. There will be no deviation between the crosshairs and the ruler at this time. If there is a deviation (parallax), you should adjust the focus carefully. The instrument or adjust the eyepiece to eliminate the focus error.

Digital level observation
The sequence of the sighting ruler for the odd-numbered stations is as follows:

a) Rear view ruler; b) Front view ruler; c) Front view ruler; d) Rear view ruler.

The sequence of sighting the scale for even-numbered stations is as follows:

A) Front-viewing ruler; b) Back-viewing ruler; c) Rear-viewing ruler; d) Front-viewing ruler.

The operating procedure of a measuring station is as follows (take the odd station as an example):

A) First, level the instrument (the telescope rotates around the vertical axis, and the round bubble is always in the center of the indicator ring);

B) Align the telescope to the rearview ruler (at this time, the ruler should be placed in the vertical position according to the circular level), aim at the center of the bar code with the vertical wire, adjust the focus until the bar code image is clear, and press the measurement button;

C) After the reading is displayed, the rotating binoculars aim at the center of the bar code of the front-viewing ruler, adjust the focus until the bar code image is clear, and press the measurement button;

D) After the reading is displayed, re-sight the front-viewing ruler and press the measurement key;

E) After displaying the reading, rotate the telescope to aim at the center of the bar code of the ruler, adjust the focus until the bar code image is clear, and press the measurement button. Display station results. The station inspection is qualified and the station is relocated.

Intermittent and detection
When the observation is paused, it ends at the benchmarking point. Otherwise, two stable, reliable, smooth and prominent fixed points that are convenient for placing the ruler should be selected at one station as the intermittent points. If there is no fixed point to choose, the turning point and ruler piles of the two measuring stations should be properly arranged before the interval (when the ruler is used as the turning point and ruler support, three wooden piles with cap nails can be used) as the intermittent point.

Intermittent testing should be carried out after the interval. Compare the height difference of any two-foot bearing point before and after the interval. If it meets the requirements of the tolerance (see Table 8), the measurement can be started from this; if the tolerance is exceeded, the height of the instrument can be changed and then tested, such as If it still exceeds the limit, it should be measured from the previous benchmark

The test results should be kept in the handbook, but not used when calculating the height difference.

The intermittent measurement of the digital level gauge can be detected by methods such as establishing a new measuring section, and the detection is carried out at a fixed point when the detection is difficult.

Observation tolerance and setting of station
Observation tolerance of station

The observation tolerance of the station should not exceed the regulations in Table 8.

How to use the electronic level and its steps

When using the dual-position automatic Anping level to observe, the Kyiv division reading difference is not calculated. For a digital level, there is no limit for the difference between the two readings of the same ruler, and the difference between the two readings is carried out by the limit of the difference between the height difference measured by the Kiev division.

The observation error of the station is beyond the limit, and it can be re-measured immediately after the station is found. If it is found after the station is relocated, it should start from the leveling point or the intermittent point (should be tested to meet the tolerance) and re-observe.

Digital level measuring section round-trip starting station setting
A) The instrument settings mainly include:

一—The measured elevation unit and the unit recorded in the memory are meters (m);

——The display position is O.000 01 m;

——Set the date format to real-time year, month, and day;

——Set the time format to real-time 24 hour system.

B) Tolerance parameter setting of measuring station:

——The high and low end of the line-of-sight tolerance;

——The high and low end of the line of sight tolerance;

——The line-of-sight difference between front and rear;

——The cumulative tolerance of the front and back line-of-sight difference;

——The tolerance of the difference between the two readings.

C) Job settings:

——Establish work files;

——Establish a test section name;

——Select measurement mode: "aBFFB";

——Enter the reference elevation of the starting point;

——Enter the point number (point name);

Input other measurement section information one by one.

D) Communication setting: operate according to the instrument manual.

Before using the electronic level, you must pay attention to the following points:
1) Do not aim the lens at the sun. Pointing the instrument directly at the sun will damage the observer's eyes and damage the internal electronic components of the instrument. When the sun is low or when the sun directly hits the objective lens, use an umbrella to block it.

2) The surface of the stripe code ruler is kept clean and cannot be scratched. The instrument converts it into electrical signals by reading the black and white stripes of the ruler. If the surface of the ruler sticks to dust, dirt or scratches, it will affect the accuracy of the plan or cannot measure at all.