It is simply impossible to imagine carrying out various construction, repair, design or installation works without measurements. More recently, standard manual roulettes were used for this. Using them is rather inconvenient, since at least two people are required to carry out the necessary measurements. The use of digital measuring instruments instead of conventional roulettes can not only greatly simplify and speed up the process, but also increase the accuracy of the measurements. Naturally, the well-known German manufacturer Bosch did not stand aside from the development and manufacture of this segment of tool equipment, releasing a wide range of such devices. One of the most popular products for this purpose in terms of price / quality / convenience is the Bosch GLM 50 laser range finder. The company produces two versions of this model, which differ significantly in functional equipment. And although both are marked Professional (that is, they are mainly intended for professional use), they are already quite popular among DIY enthusiasts.
Device and principle of operation
The Bosch GLM 50 laser rangefinder is a very compact device (slightly larger than a regular pack of cigarettes in size). In the case of the device (made of shockproof plastic) are installed:
- diode laser emitter;
- sensor-receiver of the reflected beam;
- CPU;
- liquid crystal display (with backlight);
- control buttons;
- battery compartment for installing batteries;
- threaded sleeve for mounting the device on a tripod.
The principle of operation (if you do not go into scientific subtleties) is based on a comparison of the difference in physical and technical characteristics (time delay, phase shift, and so on) of direct and reflected rays. Based on this data, the integrated processor calculates the distance with high accuracy and performs all the necessary calculations.
Modifications
The range of electronic distance meters from a well-known German manufacturer is quite wide (depending on what maximum distance you need to measure: from 20 to 250 m). The 50th model relates to medium-range devices (up to 50 m) and is presented in two versions:
- standard - laser rangefinder Bosch GLM 50 (0 601 072 200);
- with the Latin index C in the abbreviation of the name (GLM 50 C) and code (0 601 072 C00) of the device.
The accuracy of measuring linear dimensions is the same for both models. However, the latter is not only distinguished by a higher price, but also significantly surpasses the former in technical equipment and functionality.
Equipment
The standard scope of delivery for the Bosch 50 laser rangefinder (regardless of version) consists of:
- the measuring device itself;
- two batteries (AAA standard);
- a convenient nylon cover with a Velcro clip for attaching to a belt;
- detailed operating instructions (in various languages).
Warranty from the manufacturer is 12 months.
A nice bonus for potential buyers of the GLM 50 C is the minimal set of yellow targeted self-adhesive cards that help improve measurement accuracy.
Application area
According to numerous reviews, the Bosch GLM 50 laser rangefinder has become an indispensable tool for many professionals and amateurs where it is necessary to measure length, height, area or volume. It is successfully used for:
- construction and repair of buildings (or premises);
- design and installation of power supply systems, as well as ventilation;
- design of premises for various purposes;
- geodetic and landscape works;
- calculating the required amount of materials for arranging floors and ceilings, as well as finishing walls;
- control verification of the size and area of premises by specialists of the inspecting authorities;
- measurements in hard to reach places.
And when using the Bosch GLM 50 C laser rangefinder in combination with a smartphone or tablet, you can, for example, draw up a finished design project and send it directly to the customer or make an online order for the necessary building materials.
Key Specifications
The laser rangefinder Bosch GLM 50 Professional can be characterized by the following technical indicators:
- length measurement range: from 0.05 to 50 m (with accuracy: ± 1.5 mm; under adverse conditions: ± 3.0 mm);
- measurement time (standard / maximum): less than 0.5 seconds / no more than 4 seconds;
- laser radiation wavelength - 635 nm;
- power: <1 mW;
- overall dimensions: 53X114X30 mm;
- continuous operation time from one set of batteries: at least 2.5 hours;
- number of single measurements: 10000;
- weight: 0.14 kg.
Despite the fact that the Bosch GLM 50 C Professional laser rangefinder has smaller overall dimensions (45 X 106 X 24 mm) and weight (0.1 kg), you can additionally perform the following operations with it:
- measure the angle of inclination in the range from 0 to 360⁰ (with an accuracy of ± 0.2⁰);
- connect and transfer data to any mobile device (via Bluetooth or via the built-in micro-USB port).
Both models use 2 1.5V AAA batteries as a power source. To extend their service life, an automatic shutdown of the device is provided if no active actions are performed with it for 5 minutes (that is, they do not use the control buttons or move the device in continuous measurement mode).
The functionality of the "little brother"
The instructions that come with all Bosch laser rangefinders describe in great detail all the technological capabilities of the measuring device. And although all the controls are quite informative, we recommend that you carefully read it before using it for the first time.
First of all, it is necessary to establish the so-called reference line. When you turn on the device for the first time, the device is in default mode in which the reference point is the rear end of the case. At the request of the user, measurements can also be made from the front edge of the device or the center of the threaded connection to the tripod.
The basic operations that can be performed using the Bosch GLM 50 Professional laser rangefinder (and how they are graphically displayed on the instrument display) are shown below:
- length measurement (solid vertical line);
- addition / subtraction of the received data (+/-);
- continuous measurement with a change in the direction of the laser beam or the movement of the device on the surface (dashed line);
- area calculation (rectangle);
- volume determination (box);
- indirect measurement by the Pythagorean theorem (triangle).
For example, we calculate the area in accordance with the instructions for the Bosch Professional laser rangefinder:
- turn on the device;
- set the reference line (in our case, the trailing edge of the housing);
- select units;
- press the operation mode selection button several times until a rectangle icon appears on the screen;
- we press the back of the case to the wall, briefly pressing the "measurement" button;
- we do the same with the second wall of the room;
- after that, the precisely calculated area of the room will be displayed in the lower informative line of the display.
Additional features of the "older" model
In addition to the functionality described above, the Bosch GLM 50 C laser rangefinder allows you to:
- make markup with a certain predetermined step (which is very convenient, for example, when installing profiles for attaching drywall sheets);
- measure the angle of inclination of any element of the building structure.
The built-in goniometer also works as a level. Due to this, greater accuracy of the measurements is achieved. A sound signal alerts the user if the device is not installed strictly parallel to the measured surface (horizontally or vertically).
The main advantage of the 50C model over the Bosch GLM 50 Professional laser rangefinder, according to user reviews, is the Bluetooth module and micro-USB connector. By installing the necessary applications (which can be downloaded for free on the manufacturer’s website) on your mobile device (smartphone, iPhone or tablet) at your disposal, you can not only save all the measurements made (in the form of an Excel spreadsheet), but also apply them in advance prepared drawings (PDF) or photographs of the room (or structure). As a result, after a little training, the user receives not just a set of numbers stored in the memory, but a ready-made design project (taking into account interior partitions, door and window openings, ceiling heights, and so on). Taking care of the user, Bosch has developed the necessary programs for both operating systems: iOS and Android. In addition, these applications allow you to control the operating modes of the device remotely (which is very convenient when taking measurements in hard-to-reach places).
Which device to choose
When choosing a specific model, first of all, it is necessary to understand for yourself for what purposes you will use this measuring device. For those who are looking for a replacement for a standard tape roulette, it is enough to purchase a Bosch GLM 50 Prof laser rangefinder, the cost of which currently stands at 6000-6500 rubles. And although its functionality is significantly inferior to the model with the C index, the convenience and reliability of this modern device have already been appreciated by numerous users.
But professionals (for example, conducting work at several facilities), of course, prefer the GLM 50 C. And although it is much more expensive (8500-9500 rubles), its compatibility with mobile devices allows the specialist to draw up detailed drawings of the premises with the measurements taken. This greatly facilitates both the scheduling of work and the calculation of the necessary building materials.
Optional accessories
The ease of use of the Bosch GLM 50 laser rangefinder enhances its installation on a special tripod. Such a device will be very appropriate when marking up a house or a personal plot. For example, a Bosch BT 150 tripod (with an adjustable working height from 55 to 157 cm), made of high-strength aluminum and weighing only 1.5 kg, costs about 3,000 rubles. Using the fastening screw (with standard ¼ inch thread), the meter can be fastened quickly. The built-in spherical level allows you to set the range finder strictly horizontally to the ground, even on an uneven surface.
Special glasses significantly increase the visibility of the laser beam (especially in adverse lighting conditions, such as in bright sunlight). The cost of such devices, depending on the manufacturer, ranges from 300 to 1,500 rubles.
Important! Such glasses serve only for better recognition of the beam, they are not protective.
Negative factors affecting measurement accuracy
The accuracy of the measurements made with the Bosch GLM 50 laser rangefinder largely depends on the state of the surface reflecting the beam. So, significant errors can be made by structures made of glass, polished metal or porous coatings. The specifications declared by the manufacturer correspond to an air temperature of about plus 25 degrees, relative humidity not exceeding 90%, conditions of weak background illumination and sufficient reflectivity of the surface (for example, white drywall or concrete plastered wall). To increase the accuracy of measurements and minimize the influence of negative factors, special yellow sighting marks are installed on the object to which the distance is measured (they are not included in the delivery package, they must be purchased separately). The material from which they are made provides optimal reflection of the laser beam.
In conditions of high humidity, water microparticles in the air also have a negative effect and make a significant error in the accuracy of the measurements.
Important! Even with slight doubts about the correctness of the data obtained, it is better to repeat the measurements.
Advantages and disadvantages
In their reviews, users unanimously note the following advantages of the Bosch laser meters described above:
- compactness and light weight;
- simplicity and ease of use;
- clear (even at the intuition level) interface of the liquid crystal display (on which, thanks to the integrated backlight, the readings can be easily read even in low light conditions);
- high measurement accuracy, which depends mainly on the correct installation of the device before starting work;
- rubberized (and, as a result, non-slip) button control panel;
- high degree of protection against dust and moisture (IP54);
- significant mechanical strength of the case (the device retains its properties even when falling from a height of 1 m onto a stone floor).
The main disadvantages of the rangefinder (again, according to people already operating this measuring device) are:
- too "tight" nylon cover;
- lack of time stamps on data, information about which is recorded in the device memory;
- the impossibility of fixing the device at an angle in indirect length measurements.
In custody
Modern technologies are increasingly replacing conventional manual measuring devices from everyday life. Once using the laser rangefinder and appreciating its advantages, you will no longer want to use ordinary roulette. Although the warranty on the purchased device is only 1 year, the manufacturer claims that with proper operation it will uninterruptedly serve you faithfully for at least 7 years. And for such a long period, all the money spent on the acquisition will be paid off not only by a very significant saving of time for conducting various measuring works, but also by the convenience and simplicity of their implementation.