The current technology of laser measuring instruments offers a wide range that covers all requirements and satisfies all budgets. The range of distance meters, for example, is adapted to each profession and trade, starting from the basic models to the most complex ones, although all, along the scale, present the same characteristics of robustness, resistance and ease of use. concentrated in compact, lightweight and high performance instruments.
The firm Bosch currently has laser distance meters. In this article we are going to deal with the two most economical ones, with a backlit screen and specially designed for indoor measurements, where we will review the functions and characteristics that each one presents according to its respective application.
Bosch GLM 30 Laser Distance Meter
This small but powerful instrument is the perfect replacement for a tape measure and finds use particularly in household tasks, as well as in all areas where simplicity of use is desired above all else. This simplicity is such that it is reduced to a single button.
With this single button we can perform two basic operations:
- Measure distances, lengths, heights and clearances from a single reference point and in the metric system, up to 30 meters.
- Add measurement values (auto sum function).
This complete article shows us how to carry out these measurements, as well as the multiplicity of uses and applications that an instrument as simple and compact as the GLM 30 allows us.
Bosch GLM 40 Laser Distance Meter
Priced slightly higher than the previous model, the GLM 40 features a somewhat more sophisticated design, with five buttons that allow:
- Measure distances, lengths and heights from different reference points and with different measurement units, up to 40 meters.
- Take continuous measurements as you walk.
- Perform indirect measurement of lengths (by triangulation).
- Add measurement values (auto sum function).
- Subtract measurement values.
- Calculate areas and volumes.
- Save up to 10 measurements in memory.
Let’s see in more detail how the GLM 40 works, taking into account the figure below that indicates its main parts.
Once we turn on the instrument by pressing button 4, the following will be displayed by default (although it can be changed):
- Measurement mode: length.
- Reference point for measurement: rear edge of meter.
We place the instrument with the selected reference point against the desired starting point of the measurement (for example, a wall). We briefly press measurement button 2 to turn on the laser beam. We direct the laser beam towards the target surface, briefly press the measurement button 2 again to start the measurement and read the result on the screen, on the line «b» (see figure above). The laser beam will turn off automatically after the measurement is completed. When we perform multiple length measurements, the last measured results are displayed on the line “a” of measured values.
How do we change the measurement mode on the GLM 40?
For area / surface measurements: press button 9 until the area measurement indicator appears on the screen. Then we measure the base and the height, one after the other, in the same way as in the case of a length measurement. The laser beam will stay on between both measurements. After completing the second measurement, the area is automatically calculated and displayed on the result line “b” (see figure above). The individual measured values are displayed in the measured value line “a”.
For volume measurements with the EDM: press button 9 until the volume measurement indicator appears on the screen. Then we measure the base, height and depth in the same way as in the case of a length measurement. The laser beam will stay on between the three measurements. After completing the third measurement, the volume is automatically calculated and displayed on the “b” line of results. The individual measured values are displayed in the measured value line “a”.
For continuous measurements (tracking): In this case, the distance meter can be moved relative to the target, whereby the measurement value is updated approximately every 0.5 seconds. In this way, as an example, we can move a certain distance away from a wall and we will always get the actual distance reading on the screen.
To perform continuous measurements, press button 9 until the continuous measurement indicator appears on the screen. To start the continuous measurement, press button 2. The current measurement value is shown in the line «b» of results. Pressing button 2 again ends continuous measurement. The last measured value is displayed on the “b” line of results. Pressing button 2 again restarts another batch of continuous measurement. Continuous measurement turns off automatically after 5 minutes. The last measured value remains indicated in the line «b» of results. The reference point for continuous measurement is the meter base.
What other functions does the GLM 40 offer?
Deleting measurements: by briefly pressing key 4 we can erase the last measured value at any time and function. By briefly pressing the key in succession, the individual measurements are deleted in reverse order.
Adding measured values (auto sum function): we first perform a measurement or select an entry from the list of measured values. Then, we press button 8. To confirm, “+” appears on the screen. Then we take a second measurement.
Subtraction of measurements: to subtract measurement values, press key 5; on the screen, this action is confirmed with “-“. The procedure is similar to adding measured values.
As we can see, the possibilities offered by a GLM 40 are mainly aimed at professionals capable of taking advantage of all its functions at a more than reasonable price.
Therefore, once we have chosen the model we are looking for by following the corresponding guide, we can consult the table that follows, which provides a series of comparative data between the two models that we have just reviewed (GLM 30 and GLM 40 from Bosch) to decide which is the one that best suits our use, needs and possibilities.