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.
Leveling time
Approximate time it takes for the self-levelling mechanism to bring the level to a perfectly level position.
For more information on such a mechanism, see Self-Level Limits. And the actual time of its alignment directly depends on the actual deviation of the device from the horizontal. Therefore, in the characteristics, usually, the maximum alignment time is given — that is, for the situation when in the initial position the device is tilted to the maximum angle along both axes, longitudinal and transverse. Since the levels are far from being installed in this position, in fact the speed of bringing to the horizontal is often higher than the claimed one. Nevertheless, it makes sense to evaluate different models precisely according to the figures stated in the characteristics — they allow you to estimate the maximum amount of time that will have to be spent on alignment after the next movement of the device. As for specific indicators, they can vary from 1.5 – 2 s to 30 s.
Theoretically, the shorter the alignment time, the better, especially if there are large volumes of work ahead with frequent movements from place to place. However, in fact, when comparing different models, it is worth considering other points. First, we reiterate that the rate of leveling is highly dependent on the leveling limits; after all, the greater the deviation angles, the more time it usually takes for the mechanism to return the level to the horizontal. So, to directly compare w...ith each other in terms of the speed of self-leveling, it is mainly those devices in which the permissible deviation angles are the same or differ slightly. Secondly, when choosing, it is worth considering the specifics of the proposed work. So, if the device is to be used frequently on very uneven surfaces, then, for example, a model with a leveling time of 20 s and self-levelling limits of 6 ° will be a more reasonable choice than a device with a time of 5 s and limits of 2 °, since in In the second case, a lot of time will be spent on the initial (manual) installation of the device. And for more or less even horizontal planes, on the contrary, a faster device may be the best option.
Beam angle (vertical)
The sweep angle in the vertical plane provided by the level emitter. If there are several such radiators (for example, on both sides of the case), this parameter is given for each of them separately.
The sweep angle is, in fact, the coverage angle, that is, the width of the sector captured by the emitter when the line is formed. The wider this angle, the more convenient the device is to use, the lower the likelihood that the device will have to be moved up and down to build a line. On the other hand, a larger sweep angle (at the same range) requires more power — and this, accordingly, affects the cost and power consumption.
IP protection rating
The level of protection against harmful influences (in the first place — the penetration of foreign objects) that the body of the level / rangefinder provides in accordance with the IP standard. This standard describes two separate characteristics — protection against solid objects and against water. They are designated respectively by the first and second digit after the IP index; the higher the number, the higher the degree of protection.
Considering that levels and rangefinders usually have to work on construction sites where there is a lot of dust, the minimum level of protection against solid objects for such tools is the fifth. It allows some dust to get inside, but in such a way that it does not affect the performance of the device. The maximum level of dust resistance is 6, which implies complete protection from solid particles.
The second characteristic, protection against moisture, in levels and rangefinders is usually indicated starting from level 4. Officially, it provides protection "against spray from any direction", in fact this means that it can be used in moderate rain with strong winds — a useful point in that if the tool is to be used outdoors. Level 5 allows operation during storms and downpours, a device of the sixth class can withstand being hit by a wave, the seventh — a short-term immersion under water up to 1 m, and the eighth — even a long stay under water. However, for a conventional construction tool, too high water resistance i...s usually not required.
Actually, the most popular option in modern construction tools is the IP54 class: it is quite enough even for work in bad weather, while such cases are relatively inexpensive. There are also more protected models, but less often.
It is also worth noting that a certain level of dust and water protection in itself is usually provided even in devices that do not have an IP marking. The absence of this index does not necessarily mean the absence of protection — it only says that the case has not been officially certified according to the IP standard. But if you need an additional guarantee of reliability, you should still pay attention to certified options.
Operating time
Operating time of the device on one battery charge.
It is worth considering that these figures are quite approximate, since the operating time is measured under certain standard conditions (usually continuous operation at nominal power). And since in practice conditions may differ markedly, the operating time may turn out to be noticeably shorter or longer than stated. In addition, if the device uses replaceable batteries (AAA, AA and the like), then autonomy will also depend on the quality of the specific batteries/accumulators. Nevertheless, based on the data specified in the characteristics, it is quite possible to evaluate the capabilities of specific models and compare them with each other: the difference in the declared operating time, as a rule, proportionally corresponds to the difference in practical autonomy under the same conditions.
We also note that the operating time is specified mainly for levels; in rangefinders another parameter is more often used - the number of measurements (see below).
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.