Comparison Tekhmann TSL-2 vs Laserliner SuperCross-Laser 2P

The longest measurement range provided by a laser level (see “Type”) when using a special receiver with a photocell.

Thanks to its sensitivity, such a receiver is able to respond even to a weak laser beam, the mark from which is no longer visible to the naked eye; At the same time, the area of the photocell is quite large, and special indicators make it possible to determine the exact position of the mark. Among other things, this significantly expands the range of action of the level - the measurement range with a receiver is usually several times greater than without it. On the other hand, such equipment inevitably affects the overall cost of the device; and in some models the receiver is not included in the package at all; it must be purchased separately. However, the second option also has its advantages: you do not need to immediately pay for an additional accessory, it can be purchased later, when a real need arises, while some models allow you to choose the optimal receiver model from several options at your discretion.

Note that the receiver can be useful not only for increasing range; These points are described in detail in paragraph “Included parts”.

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.

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.

Class of the laser emitter installed in the device.

The laser power primarily depends on this indicator; and this, in turn, affects the effective range of the device and precautions when working with it. The main options relevant for modern levels and rangefinders are class 2, class 2M and class 3R, here is their more detailed description:

— 2. Such a laser beam is considered safe in case of accidental contact with the eyes, since due to the blinking reflex, the exposure time in such cases usually does not exceed a quarter of a second. This applies to both the naked eye and the use of magnifying instruments such as a monocular or even a telescope. But constant exposure to the eye already poses a danger to vision. The power of such emitters should be below 1 mW. In fact, 2 is the lowest (in terms of power) class used in levels and rangefinders; weaker lasers of classes 1 and 1M simply do not provide the required efficiency. Such emitters are used in the vast majority of low and medium power devices.

- 2M. Such lasers produce a wider beam than class 2 emitters. However, such a beam is also considered safe if it accidentally enters the eye - but only if we are talking about the naked eye. When viewed through a monocular or other magnifying optical instrument, class 2M lasers are dangerous even with low-term (fractions of a second) exposure to the eye. I...n general, this option is quite rare: class 2M is not strictly official and does not have such clear criteria as the original class 2.

- 3R. Also known as IIIa. In fact, it is an analogue of class 2, suggesting a higher emitter power, namely from 1 to 4.99 mW. At the same time, class 3R lasers are generally considered safe in case of accidental contact with the eye when a person reflexively blinks or turns away and the exposure time does not exceed ¼ second. However, such emitters carry a greater risk of serious harm to health than Class 2 devices, so greater caution should still be exercised when using them.

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.

The sweep angle in the horizontal plane provided by the level emitter. If there are several emitters, their total coverage angle is indicated here; a typical example of such devices are models for full 360 °, not related to rotation.

Actually, all rotary devices, by definition, provide a coverage of 360 °. Therefore, it is worth paying attention to this parameter in cases where we are talking about more traditional laser levels. And here it is worth considering that a larger coverage angle, on the one hand, can provide additional convenience, on the other hand, it increases the price and power consumption of the device. So when choosing, you should proceed from real needs; detailed recommendations on this subject can be found in special sources.

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.

Zenith in this case is called a point projection directed vertically upwards.

By itself, such a projection can be useful, for example, if you need to make holes in several floors, located strictly one above the other. It is enough to point the "anti-aircraft" laser at the hole located directly above it — and the mark from the beam that passed through this hole will indicate the point for the hole on the next floor. And if the device also has the nadir function (see below), then the combination of these functions will be very convenient for marking the floor and ceiling at the same time — for racks, partitions, etc.: marks from the zenith and nadir are located strictly one above the other.