When performing construction work, a construction level is often necessary, but those who use it may not know that periodic verification of the accuracy of the device is required. To check the accuracy, you need to know how to do it correctly, because you can not be completely sure of the correctness of the readings of the laser level.
The laser level allows building measurements with the highest possible accuracy.
Accuracy is one of the main characteristics of the device. Experts recommend checking the accuracy of the measuring device every 2 or 3 months. If during storage of the device there are difficulties, as well as during transportation of the device or its operation, then they can cause disruptions in its operation.
What should you know to conduct a quality check of the level accuracy?
Any measuring device has an appropriate measurement error for its model. The laser level, which is suitable for carrying out qualitative measurements, may have an error of at most 0.2 mm / m. Many well-known and conventional enterprises produce cheap laser levels (priced from $ 50 to $ 200). These are devices having an amateur class, the permissible error of which is 0.5-0.8 mm / m.
The main functions of the household laser level.
If you take into account the laser level, which has a manual alignment based on the bubble level, then there is the likelihood of inaccurate measurement and verification. To check the horizontal plane, you will need the laser level itself, mounted on a special tripod with a height adjustment lever. To check the accuracy, the device is installed close to the walls on which you want to apply labels.
The level works in two planes. One is horizontal and is denoted by the letter X, and the second (vertical) is Y. Manufacturers of devices often mark these letters on the top of the case of measuring devices. In the absence of signs and the need to first check the device letters on the case should be noted most.
The laser level is checked according to the instructions.
The horizontal plane should pass at the top of the level, it is denoted by the letters X and Y, respectively. Two axes are marked accordingly on the top of the device. Each beam must have a proven axis. It is calibrated, if necessary, using instructions or contact the service center of measuring devices.Back to table of contents
How to check the accuracy and calibrate the laser level?
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The stages of checking the accuracy of the device
The process of measuring the radiation of the instrument on the accuracy of the laser level.
Measurements of the instrument's radiation on the laser level accuracy are associated with three points based on the verification:
- Beam horizontally (x).
- Beam vertically (Y).
- The slope of the plane.
To carry out a test, the measuring device operates according to a scheme that provides for the following procedure, which allows to verify the accuracy:
- Check the X and Y axes to find out which one requires calibration, since one of them may be correct, and the second one is not.
- They check the Y axis on both sides, continuing the test with its correct calibration on both sides, and the X axis is checked relative to the Y axis.
- Check the X and Y axes against each other to compare their positive and negative values.
It is necessary to separately consider all stages of the inspection of each axis.
To check the horizontal beam X, perform the following steps:
Installation sites of a laser tape measure for measurement.
- Place the device on a tripod or place it on a plane so that it is at a distance of 30 m from the wall, and beam X goes out onto the wall.
- Turn on the device.
- Make a mark corresponding to the level through which the center of the beam passes.
- If the light is too bright, they use a laser receiver.
- Turn the device through 180 °, directing a horizontal beam X to the wall.
- Mark the position of the center of the projection X near the first mark, observing one line for two marks.
- The laser level must have an accuracy that meets all the characteristics that are provided by the manufacturer.
- When the mark is in the range of the corresponding characteristics, the X-ray calibration is not required. After that, proceed to check the second beam Y.
- At the end of the horizontal plane test, the difference is measured, which is the actual deviation characterizing the position of the points: one is marked first, and the second is last.
The resulting deviation should not be greater than the value specified by the instrument manufacturer.
To check the Y axis, the following actions are performed:
The principle of operation of the laser level.
- Turn the device at a right angle. The direction of the beam Y must coincide with the location of the wall.
- Next, mark the position for the center of the projection using a laser radiation receiver, if there is a need to suppress bright light.
- Then the level is rotated by an angle of 180 °, reversing the Y mark with a positive sign on the wall.
- After it should be noted the point at which the center of the projection is in view of the first mark.
- After checking all the characteristics, the resulting mark is compared with the stated accuracy of the device.
- At the location of the mark in the interval provided by the instruction for the Y axis, calibration is not performed.
- Then continue to check the point X, which is the last in relation to the point Y.
Verification of the accuracy of the device vertically and inclination of the plane
In order to conduct a test in the projection, the vertical level is turned at right angles to the position in which the horizontal plane is checked. All other measurements are carried out similarly, which is associated with obtaining a deviation that is less than the accuracy specified by the manufacturer of the device.
Installation scheme of a laser device to ensure measurement accuracy: 1 - laser device, 2 - specified starting point of the alignment, 3 - initial mark, 4, 8 - racks of marks, 5 - laser beam, 6 - specified ending point of the alignment, 7 - final mark.
Before checking the accuracy of the device by tilting the plane, the device is installed between two walls in the very center if the distance between them is small, for example, 5 m. Next, the device is turned on to put a mark on the wall using the available method of intersection of laser beams. Then they rotate the level by 180 ° along the vertical axis, after which the mark is again made at the point of intersection of the projections.
The next stage of verification is associated with the transfer of the level close to the wall. When this happens, the length of the distance between the device and the wall decreases to 0.5-0.7 m. The same marks are made the second time. After checking the accuracy of the device, they begin to compare the marks with regard to their difference modulus. It should show that the difference in marks does not exceed the value that shows the accuracy of the laser level, declared by the manufacturer.
You can give an appropriate example of the calculation of the modulus of the difference. If it is 3 mm, that is, (a1 - a2) = 3 mm, and (b1 - b1) = 5 mm, then the error can be calculated using the formula: | (a1 - a2) - (b1 - b1) |. Thus, | 3 - 5 | = 2 mm, therefore the declared error is compared with the result equal to 2 mm.
Checking the level can be associated with the detection of deviations in excess of the value set by the manufacturer, so correcting the device with your own hands is not recommended. The level is too complicated a device: it is not realistic to calibrate its axes at home. Contact a service center specialist for help.Back to table of contents
How to check the linear self-leveling laser level?
The level equipped with a pendulum mechanism is the most used type of measuring device in construction. To verify its accuracy, the following operations should be carried out:
- You can perform the first test by checking the accuracy of the device, taking into account the inclination to the side of the horizontal projection.
- The level is installed at a distance equal to 2-4 m from the wall. Then using a pencil make a mark, given the level of passage of the beam.
- Next, the laser level is rotated to the right around the axis, leading the beam to the mark with the left edge. Then the right edge of the beam is brought to the mark in the opposite direction.
If the beam remains on the mark, then the laser level can be considered accurate. When moving the beam up or down from the mark itself, the plane of the beam deviates to the right or left.
After that, they switch to another test, which allows to check the accuracy of the laser level, checking the angle of inclination of the plane backward or forward. To install the device using a tripod that you want to install near the wall. Then it is turned on, the level is turned to the wall and the beam is marked with the number 1 mark.
Turning the device 180 ° around the axis, put the mark number 2 on the second wall. If you provide a distance from one wall to another, equal to 3-4 m, then it will be sufficient to verify the accuracy of the laser level. Further, the device is rearranged closer to the wall, which is located on the other side, so that the projection of the beam can accurately fall to the mark No. 2 with the appropriate height of the tripod.
Then the laser is again turned 180 ° to check the coincidence of the beam with the mark number 1. If there is a match, then the operation of the device is accurate. When the beam is positioned below or above the mark, the plane of the level reverses backward or forward.