Measurement range
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.Accuracy
Accuracy is described as the maximum deviation from the true value of the measured parameter, which the device can give if all the rules for its operation and the corresponding measurements are observed. In both rangefinders and levels, this parameter is usually designated for a certain distance — for example, 3 mm at 30 m; but even for one manufacturer, these "control" distances may be different. Therefore, in our catalog, the accuracy of all devices is recalculated for 1 m distance; with such a record, for the example above, it will be 3/30 \u003d 0.1 mm / m. This makes it easier to compare different models with each other.
It is also worth mentioning that the meaning of the "accuracy" parameter for different types of measuring instruments (see "Type") will be different. For optical levels, it is described in the "SKP" paragraph above. For laser levels of all types, accuracy is the maximum deviation of the mark from the true horizontal (or vertical, if such a function is provided), and for the horizontal, we can talk about both moving the mark up / down and turning it. In rangefinders, this characteristic describes the maximum difference (both in "plus" and "minus") between the readings of the device and the actual distance to the object.
Anyway, the smaller the error, the better; on the other hand, accuracy significantly affects the price of the device. Therefore, it is necessary to choose a specific model for this parameter, taking into account the...specifics of the planned work. For example, for a relatively simple repair in a residential apartment, a high-precision tool is unlikely to be required; and recommendations for more complex tasks can be found in specialized sources, ranging from expert advice to official instructions.
Tripod thread
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.
Vertical projections
The number of vertical projections issued by the laser level during operation.
Most modern levels are designed for a strictly defined position when working; accordingly, the
projection is called vertical, carried out from top to bottom relative to the standard position of the device. If there are several such planes, the level can be used for two or even three walls at once — this is useful, for example, for the simultaneous work of several people. At the same time, there are portable devices that can be used in different positions; for them, the main working plane is called vertical, although during operation it can be located both horizontally and at an angle, depending on specific tasks. Also note that the vertical projection can also give a horizontal line — for example, when installing a level on the floor.
Note that the number of projections is calculated not by geometric planes, but by individual laser elements, each of which is responsible for its own “work area”. For example, if the level has two vertical elements located at opposite ends and directed in different directions, they are considered as two projections even if these projections lie in the same plane.
Point projections
The number of individual points projected by the laser tool — rangefinder or level, see "Type" — when working. In the first case, one
point projection is standardly provided — more is simply not required to measure distances. In levels, there can be several points, and some models do not have planar projections at all and work only with points. This format may not be as convenient as displaying lines; at the same time, with the same laser power, dot marks shine brighter and are more visible, especially at long distances. In addition, there are certain types of work for which point projection is considered optimal — for example, laying sewers, determining the locations for two holes in opposite walls, etc.
Manual prism adjustment
The ability to change the operating mode of the laser level by changing the position of the prism that scatters the laser beam. To be more precise, this function allows you to switch the same emitter to different modes: vertical, horizontal, cross-shaped, dot. The specific set of these modes may be different, depending on the model, but anyway, it should be borne in mind: manual prism adjustment is very poorly combined with high-precision mechanisms. Therefore, this function can be found only in the simplest models, designed exclusively for simple everyday tasks and not providing for special accuracy.
Built-in mechanical tape measure
Traditional
mechanical tape measure, built right into the body of the device.
This function is most popular among laser rangefinders: a tape measure is also intended for measuring distances, its use allows you to save battery power, and in some cases a flexible metal tape is even more convenient than a laser. Note that such devices usually do not look like rangefinders with additional equipment, but rather like traditional tape measures, supplemented by a laser.
Also, such equipment can be found in separate laser levels — mostly simple and inexpensive models designed for purely domestic use.
Power source
The type and number of batteries used in the level/distance meter. All elements of standard sizes (
AA,
AAA,
C,
D,
PP3) are available in two formats — disposable batteries and rechargeable batteries. This gives the user a choice: either buy relatively inexpensive batteries every time, or invest once in a rechargeable battery with a charger, and then simply charge the battery as needed.
Branded batteries are, by definition, made only rechargeable, as are
18650 batteries.
Specific types of power today can be as follows:
— AA. A standard battery, known as a "finger battery". The power of these batteries is average, they can be used both in simple and quite advanced devices. This power supply is convenient due to the fact that AA batteries are very widespread and sold almost everywhere — due to this, finding and replacing them is usually not a problem.
— AAA. A smaller version of the AA element described above — almost identical in shape, but thinner and shorter. Such elements, known as "mini-finger" or "little fingers", have a rather low capacity and power, but are useful for portable devices, where compactness is crucial. They are also quite widespread.
— C. A cylindrical element, in the form of a rather thick "bar
...rel" — with a length of 50 mm, the diameter is 26 mm. Due to its higher capacity and power than AA, it is better suited for advanced models with "long-range" lasers, but is less commonly used and generally less common.
— D. The largest and most capacious type of standard batteries found in modern levels and distance meter: thickness and diameter are 62 and 34 mm, respectively. The main area of application for D batteries is powerful professional devices.
— Rechargeable battery. In this case, the tool is powered by an branded battery that does not belong to any standard size. This option is good because such batteries are initially created for a specific model of the level/distance meter and are supplied in the set (and in some models they are made non-removable); in addition, their specifications can significantly exceed those of standard elements of a similar size and weight. On the other hand, such power source is less convenient when the charge runs out at the wrong moment: the only way to remedy the situation is usually to recharge, and it takes quite a long time (whereas standard batteries can be replaced in just a minute).
– 18650. The name of these batteries comes from their dimensions: 18.6x65.2 mm, cylindrical, outwardly they resemble somewhat enlarged AA batteries, but they have an operating voltage of about 3.7 V and a higher capacity. In addition, all 18650 type batteries are by definition not disposable, but rechargeable batteries (lithium-ion type).
— PP3. 9-volt batteries of a spesific rectangular shape, with a pair of contacts on one of the ends. Due to the high operating voltage, they provide high power and actual capacity, so one such battery is usually enough for operation.
— LR44. Miniature batteries of "coin" type, 11.6 mm in diameter and 5.4 mm thick. Usually installed in sets of 3 and are used in compact low-power laser levels, for which small size is more important than power and capacity. Note that specifically the LR44 marking refers to relatively inexpensive alkaline batteries; more expensive and advanced silver-zinc power supplies are referred to as SR44, or 357.
— 23A12V. A rather rare option: cylindrical batteries (length 29 mm, diameter 10 mm) with a nominal voltage of 12 V.In box
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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.
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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)”.
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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.
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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.