Comparison Bosch GLM 50 C Professional 0601072C00 vs Bosch PLR 40 C 0603672320

The range at which the device remains fully operational without the use of additional receivers (see below); in other words, the radius of its action without auxiliary devices.

In some models, a range may be specified that shows the minimum ( 3 cm, 5 cm) and maximum measurement ranges. But in most cases, only the maximum value is indicated.

The specific meaning of this parameter is determined by the type of instrument (see above). So, for optical levels, the measurement range is the greatest distance at which the operator can normally see the divisions of a standard leveling staff. For laser levels, this parameter determines the distance from the device to the surface on which the mark is projected, at which this projection will be easily visible to the naked eye; and in rangefinders we are talking about the greatest distance that can be measured. Typically, the measurement range is indicated for ideal conditions - in particular, in the absence of impurities in the air; in practice, it may be less due to dust, fog, or vice versa, bright sunlight "overlapping" the mark. At the same time, tools of the same type can be compared according to this characteristic.

Note that it is worth choosing a device according to the range of action, taking into account the features of the tasks that are planned to be solved with its help: after all, a large measurement range usually significa...ntly affects the dimensions, weight, power consumption and price, but it is far from always required. For example, it hardly makes sense to look for a powerful laser level at 30-40 m if you need a device for finishing work in standard apartments.

Measuring accuracy provided by a laser distance meter (see "Type")

This parameter is traditionally indicated by the error - the maximum deviation of the obtained results from the actual values, which may occur due to the imperfection of the device. The physical features of laser rangefinders are such that in such devices the error is practically independent of the measured distance. Therefore, the accuracy of such rangefinders is indicated in millimeters. At the same time, in our time, models are generally considered to be high- precision, where this indicator does not exceed 1.5 mm (in some models it is only 1 mm); but even in relatively simple and inexpensive devices, deviations of more than 3 mm are practically not encountered.

The general selection rules for this indicator are traditional: the more accurate the device, the more expensive it is, as a rule. In addition, we emphasize that for everyday and even many professional tasks, the difference described above is not fundamental in accuracy. Therefore, it makes sense to specifically look for a rangefinder with a minimum error in the case when the measurement accuracy “to the millimeter” is fundamental. At the same time, it should be borne in mind that for such measurements, appropriate accuracy in the placement and use of the device itself will be required - otherwise, all the advantages will be nullified by errors from incorrect installation and operation.

The number of reference points provided in the rangefinder (see “Type”).

The reference point is called “conditional zero” - the point from which the device begins to measure distance. If the device states only one reference point, then this is, as a rule, the rear edge of the case. However, there are few such models on the market, mostly the simplest and most inexpensive rangefinders. Devices with two such points are much more popular - usually the rear and front edges of the case. There are also more advanced options - three or even four reference points. In the first case, the role of an additional conventional zero is played by either a folding stop bracket or a mounting point on a tripod; and the second usually provides both a bracket and a tripod socket.

In any case, a larger number of reference points provides more measurement possibilities, but increases the cost of the device.

The temperature range at which the device is guaranteed to work for a sufficiently long time without failures, breakdowns and exceeding the measurement error specified in the characteristics. Note that we are talking primarily about the temperature of the device case, and it depends not only on the ambient temperature — for example, a tool left in the sun can overheat even in fairly cool weather.

In general, you should pay attention to this parameter when you are looking for a model for working outdoors, in unheated rooms and other places with conditions that are significantly different from indoor ones; in the first case, it makes sense to also make sure that there is dust and water protection (see "Protection class"). On the other hand, even relatively simple and "myopic" levels / rangefinders usually tolerate both heat and cold quite well.

The standard size of the thread used to mount the level/rangefinder on a tripod (if available). This option can be useful if you already have a surveying tripod that you want to use with the tool.

The most popular options in modern devices are 1/4" and 5/8". It is worth noting that 1/4" is a standard size for photographic equipment - accordingly, levels with such a thread can be installed even on ordinary photographic tripods.

The functions of the rangefinder allow you to more comfortably perform work and not calculate various mathematical formulas, but with one button to get the result after the measurements have been taken. Among such assistants there are area / volume measurement, indirect measurements (Pythagorean theorem), tilt angle measurements, height measurement, trapezoid measurement, addition / subtraction, min. / maximum values, continuous measurement (tracking), countdown timer, layout mode, painter mode, memory of the last measurements and others. More about them:

— Measurement of area/volume. Built-in software tool for measuring the area and / or volume of premises or large objects. This function works as follows: the user only needs to measure the length, width, and for volume, also the height of the object, after which the rangefinder will independently multiply the received data and display the final result.

— Indirect measurements (Pythagorean theorem). A function that allows you to determine the length of one of the sides of a right triangle from its othe...r two sides. One of its most popular uses is to measure the height of buildings, walls, poles, and other objects without having to approach them. To do this, you need to place the rangefinder at ground level and measure two distances from this point: to the foot of the object, horizontally (one of the legs) and to the top of the object (hypotenuse). Based on the Pythagorean theorem, the device will automatically calculate the length of the second leg - that is, in this case, the measured height.

— Measuring the angle of inclination. A feature that turns the rangefinder into an advanced level. When it is turned on, it is enough to attach the device with its side to an inclined surface or other similar object - and the built-in sensor will automatically determine the angle of inclination, displaying it on the display.

- Height measurement. A special mode for measuring the height of various objects. Note that in many devices this function is actually performed by indirect measurements according to the Pythagorean theorem (see above). Therefore, the possibility of measuring height is indicated mainly in tech models that have more advanced capabilities for such measurements. A typical example is an extended version of the Pythagorean theorem, which is used when a rangefinder is mounted on a tripod at a certain height from the ground. With this placement, to measure the height, you need to take three measurements: the distance to the foot of the object (the rangefinder will be tilted down), to the object horizontally and to its top. According to the data received, the device will build two triangles, perform the necessary calculations and give the final height value.

- Measuring the trapezoid. A function that allows you to determine the length of the fourth side and the total area of the figure from three sides of a rectangular trapezoid. It is mainly used to calculate the area of walls and facades in houses with sloped, gable and other similar roofs. If the upper part of the wall has a slope to one side, to determine the area, it is enough to measure the length of the base and the height of the two sides adjacent to the edges of the roof. If the upper part of the wall adjoins a gable roof, the wall must be divided into two trapeziums and measured using the same procedure; a similar method can be used with roofs of more complex shape, due to which the upper side of the wall looks like a broken line.

- Addition / subtraction. Possibility to sum the results of measurements, as well as to subtract one result from another. One of the simplest computing functions - which, nevertheless, can make life much easier for the user.

— Min. / maximum values. In this mode, the device takes a whole series of measurements at a short interval, and then displays the smallest or largest of the obtained values. As a rule, modern rangefinders provide for both formats of operation (both minimum and maximum), which is why they are combined into one function. However, the meaning of these options is different. So, the maximum value allows, among other things, to accurately determine the size of the room: it is enough to place the device in the corner, turn on the appropriate mode and slowly draw the laser horizontally in the region of the opposite corner; the largest distance obtained will be the length of the size. In turn, the minimum value can be useful, for example, to measure the length of the perpendicular to the wall; the measurement technique here is similar, and the smallest number obtained will just correspond to the length of the perpendicular.

— Continuous measurement (tracking). In this mode, the device continuously takes measurements at a sufficiently high frequency (usually 1 - 2 times per second), displaying the corresponding results on the display. This format of work is also called "roulette mode", it allows you to constantly track the distance from the rangefinder to a specific object. This can be useful, for example, if you need to accurately measure the distance from a wall, pole or other landmark: instead of taking several measurements, trying to “get” the device into the right position, just turn on tracking and move the rangefinder until the desired distance value is not displayed.

- Countdown timer. A function that allows you to automatically take measurements after a specified period of time. A kind of analogue of shooting on a timer in cameras: just point the device at the desired point, turn on the countdown - and at the end of it the device will work itself. The countdown is mainly used to eliminate the twitching of the body, which inevitably occurs when measuring manually (at the touch of a button); this is especially useful for high precision measurements and/or when using the instrument from a tripod or other stand.

- Markup mode. A mode that allows you to divide a particular segment into sections of a certain length - for example, under posts for a fence. The specific implementation and capabilities of this mode may be different, these nuances should be clarified in the instructions for a particular device. So, in some devices, you can measure the total length of the segment, set the number of identical sections - and the electronics will calculate the length of each part. In others, you can manually enter the length of the segment, or even several options for their length at once (for example, the distance from the starting point to the first mark and further gaps between marks). In any case, in the marking mode, the rangefinder works in the same way as the tracking described above - constantly taking measurements and displaying the current result on the display. And when measuring, the device must be smoothly moved along the marked line; when the next mark is reached, a signal will be given.

- Painter mode. A mode designed to calculate the total area of walls (internal in the room or external in the entire building). Such an opportunity is especially convenient for painting work (hence the name), as well as other similar tasks - wallpapering, laying tiles, external insulation, etc. The “painter mode” is implemented, as a rule, as follows: using the device, the master first measures the total perimeter of the walls, then their height (or vice versa), after which the electronics automatically calculates and gives the final value.

— Memory of the last measurements. The ability to save the results of the last few measurements in the memory of the device. In most models with this function, the memory of the last measurements is included initially, the user does not need to specifically change any settings. The convenience of such a memory is obvious: it allows, if necessary, to return to previous results and clarify a particular value without repeating the measurement. It is only necessary to bear in mind two points. Firstly, the number of memory cells can be different - as a rule, it is in the range from 20 to 100 and is indicated here, right under the words "memory of the last measurements." Secondly, when these cells overflow, the newest results are automatically overwritten in place of the oldest ones; and such a function as protecting individual cells from overwriting is usually not found in laser rangefinders (although exceptions are possible - this point should be clarified in the documentation for a particular device).

- Calculator. A traditional calculator that allows you to perform various calculations at the request of the user. These can be both operations with data obtained during measurements, and operations with numbers entered manually.

— Horizontal mode Smart. "Smart" mode, which allows you to measure and calculate a whole range of dimensions and angles, literally on the spot. A typical example of the implementation of Smart looks like this: a rangefinder from the same point measures two distances to a wall or other similar object - one is the smallest (along the perpendicular), and the second to a certain point “nearby”. After that, based on the received data, the device calculates the angle of rotation and the distance between the points. Other, more specific functions are also possible.

— Measurement of inclined objects. Various additional functions related to the measurement of inclined objects (in addition to determining the angle of inclination described above). The specific set of such capabilities may vary; they should be specified separately.

We also note that in modern rangefinders there may be other possibilities, in addition to tech listed above.

— holder. Devices for fixing the level / range finder on various surfaces. Such a device differs from a tripod primarily in its small size — within a couple of tens of centimeters. On the other hand, most holders allow you to install the device not only on horizontal, but also on vertical surfaces — for example, walls (and some are exclusively wall-mounted). Anyway, this function greatly expands the installation possibilities.

— Receiver. laser radiation supplied with the device. This device is usually equipped with laser levels, less often with rangefinders, and it is not required at all for optical instruments. The main purpose of the receiver is situations where the laser mark is not visible to the naked eye — for example, at a long distance or in bright light. More details on the features of its application are described above in the paragraph “Measurement range (with receiver)”.

— Tripod. Most modern instruments have a standard size thread and can be used with any suitable tripod. On the other hand, a complete tripod is most often specially designed for a certain model and optimally matches it in terms of general characteristics. In addition, this configuration option relieves you of the need to look for and purchase a suitable tripod yourself.

— Case / case. The main function of these devices is to protect...the device from bumps, scratches, dirt, temperature changes and other adverse effects; for this, of course, improvised means can also be used, but specialized protection is usually both more convenient and more reliable. In addition, almost all cases and most covers greatly simplify the transportation of the tool — in particular, due to the fact that they can also be used for complete accessories.

— Remote control. Among rangefinders and optical levels, this function is practically not found, because. working with them involves the constant stay of the device in the hands of the operator. But for laser levels that require you to regularly move from the device to the surface to be marked and back, the remote control can be a very useful addition — due to the fact that it minimizes such movements. For example, after marking the "front of work" on the wall according to the projection from the level, you do not have to approach the device to turn it off — just give a command from the remote control. At short distances, the savings in time and effort may not be so obvious, but over large areas, they can become quite noticeable.