Comparison Tekhmann TAG-125/i20 Kit vs Einhell Expert Plus TE-AG 18/115 Li Kit (1x3.0 Ah)

The speed of rotation of the working attachment, which is capable of providing a grinder of the appropriate design (for example, angle — see "Type"). If the device has speed control, this paragraph shows the range of such adjustment, from minimum to maximum.

It makes sense to compare by this parameter units belonging to the same type and having the same maximum diameter of the disk (or other working nozzle). The latter is due to the fact that the larger the disk, the faster its edge moves (at the same speed); i.e. a larger diameter requires less RPM for the same performance/efficiency. In general, when comparing different models, the following should be taken into account. The higher rotation speed is well suited for large volumes of work (because it improves productivity) as well as for fine polishing with “delicate” nozzles. A lower setting, in turn, improves accuracy (reduces the chance of removing excess material), as well as provides more torque and allows you to more effectively deal with hard, stubborn materials. More detailed recommendations for different types of work and different nozzle diameters can be found in special sources; here we note that an increase in the rotation speed, usually, affects the cost of the machine compared to analogues (since this requires a more powerful engine). In addition, discs and other attachments may have maximum RPM limits.

The maximum disc size that can be installed in a grinder of the appropriate design (see “Type”). Most models are capable of working with nozzles of smaller diameter, but a rim that is too large simply will not fit on the tool due to size limitations.

The larger the disc, the larger the processing area and the depth of cut provided by the grinder. On the other hand, rotating a larger attachment requires corresponding power, which, in turn, affects the price, dimensions and weight of the entire tool. So you should choose according to this parameter taking into account the specific tasks for which you plan to use the machine. Detailed recommendations on this matter can be found in special sources; Here we note that discs are conventionally divided into small (up to 125 mm), medium (up to 230 mm) and large (230 mm or more).

— Soft start. A function that provides smooth spin-up of the grinder motor, with relatively little acceleration. This is achieved by limiting the starting current. The soft start serves two purposes: it prevents the tool from jerking, reducing the risk of letting it go, and it reduces the load on the mains, avoiding large power surges.

— Speed controller. Possibility to limit the maximum number of engine revolutions. In fact, this function is a smooth speed control; it is useful when full speed is not required, such as delicate jobs where accuracy is more important than productivity. Note that this function is found in all types of grinders — including those with a vibration or belt principle of operation (see "Type"): even in such units, the vibration frequency or belt speed is determined precisely by engine speed.

— Maintain momentum. The ability to maintain a given number of revolutions regardless of the load on the working nozzle. This function is implemented by automation, which accordingly adjusts the engine power — increases it with an increase in load and reduces it with a decrease. A constant rotation speed has a positive effect on both the quality of processing and the service life of the working nozzles and the entire tool.

— Protection against accidental activation. The ability to block the power button,...preventing it from being accidentally pressed. This allows you to safely move the switched off tool from place to place during work breaks without fear of accidentally turning it on. Also, this feature will be useful if there are small children nearby. And in some models, the protection can also turn on when the power is turned off (for example, network failures) — thanks to this, when the power is restored (which can happen at the most unexpected moment), the tool will not start working without the user's command.

— Electronic engine protection. A safety system that turns off the tool when the load on it increases critically. The specific way in which such protection works may vary. For example, in some models, it turns off the engine with a sharp increase in the load on the working nozzle — for example, when the disc is jammed in the material; this avoids sharp jerks of the tool, its breakage, disc destruction and other unpleasant consequences. In other models, protection reacts to overheating or a critical excess of current. There are also tools that combine both of these options.

— Brushless motor. The presence of a brushless motor in an electric grinder (see "Power supply"). Such motors are considered more advanced than traditional collector motors (with brushes): they are more economical in terms of energy consumption, less noisy and do not spark, which is important in conditions of increased fire danger. The main disadvantage of brushless motors is their high cost.

— Engine brake. A special brake that stops the rotation of the motor shaft after power is turned off. Thanks to such a device, after finishing work, you do not need to wait until the grinder nozzle finishes rotating by inertia — the rotation stops in just a couple of seconds (whereas without a brake, this may take several tens of seconds). This not only increases the safety of work, but also has a positive effect on the service life of the tool.

— Safety clutch. A protective clutch that prevents damage to the engine when the load on it is significantly increased — for example, in the event of a jammed disc. Such a coupling connects the working nozzle and the motor shaft. It can be disposable or reusable: in the first case, when overloaded, the clutch is destroyed and needs to be replaced, in the second, it is disconnected, and to continue working, it is enough to connect it back.

— Backlight. This feature is definitely desirable when working in low light conditions. However, it can also come in handy in bright external light: the place of work is often in the shade (for example, from the instrument itself), and it can be difficult to work in such conditions without special lighting.

— Display. Own display, which can display various information about the operation and status of the device. Such a screen provides additional convenience and visibility, but in general this is a rather specific function that is extremely common in modern power tools.

— Synchronization with a smartphone. The ability to connect the instrument to a smartphone or other gadget (such as a tablet) via Wi-Fi or Bluetooth. Such a connection is usually used to adjust the operating parameters; doing this through a mobile application is often more convenient than through the controls on the instrument itself.

— Anti-vibration system. Damping system that reduces the level of vibrations that occur during operation. The presence of such a system has a positive effect on both the quality of work and convenience: strong vibration of the tool leads to rapid fatigue, the anti-vibration system helps to avoid this.

— Rotary main handle. The possibility of turning the main handle of the grinder around the longitudinal axis. This function is found mainly in corner models (see "Type") — it provides additional convenience, allowing you to adjust the position of the handle to the specific situation. This can be important for working in non-standard positions and hard-to-reach places.

— 3-position additional handle. An additional handle mounted on a removable mount and having three installation options: on the left (traditional option for right-handed holding of the tool), on the right (for left-handers) and on top (for specific cases — situations when you need to periodically change the grip, work in hard-to-reach places, etc.). P.). This feature provides advanced options for customizing the instrument to your own preferences. It is found mainly in corner models (see "Type").

— Keyless disk replacement. The ability to change discs in a grinder (usually an angle grinder, see "Type") without the use of keys and other additional tools. The convenience of this function is obvious: you do not need to keep the key with you all the time, make sure that it is not lost, etc. However the keyless mount is considered somewhat less reliable than the key mount, so it is rarely found in heavy professional models.

— System of fastening X-LOCK. An advanced attachment system used on some angle grinders (see "Type"), predominantly manufactured by Bosch and Makita. This system is somewhat more expensive than the traditional 22mm nut or washer mount, but has a number of advantages over it. Firstly, X-LOCK provides the simplest and fastest installation: no need to fiddle with additional parts or tools, just put the disk on the spindle and press it until it clicks; in turn, to remove the working nozzle, it is enough to press the button that turns off the latch. Secondly, you can install the nozzle with only one, correct side to the tool — the mounting design will not allow otherwise. The main disadvantage of machines with this system is incompatibility with cheaper and more common discs for a standard 22 mm mount; and equipment for X-LOCK is not yet available in every hardware store.

— Collet chuck. Special design chuck used in straight grinders (see "Type"). The clamp of such a cartridge consists of several elastic petals (usually 2 – 3), which, when tightened, are compressed, fixing the working nozzle. The main advantages of collets are the speed and convenience in changing nozzles, simple design and low cost.

— Coolant supply(coolant). Possibility of supplying coolant to the place of work. This function is found mainly in machines for stone and concrete (see "Type"), because it is for these materials that water cooling is most relevant: it not only prevents overheating, but also prevents the formation of dust. To supply water to the machine, a nozzle is provided, which is led to the working nozzle, and a pipe for connecting to a water hose.

— Connecting the dust collector. The ability to connect a container to the tool to collect dust and other contaminants that occur during operation. Such a container can be supplied with the machine, but this is not necessary, this point should be clarified separately. Anyway, the dust collector, although it does not provide one hundred percent protection against pollution, however, significantly reduces their amount and facilitates cleaning after work. Dust collectors can be both reusable and disposable.

The name of the battery platform supported by the instrument.

The battery platform is a battery standard used to keep different power tools and other equipment of the same brand (pressure cleaners, flashlights, etc.) could use the same power supplies and chargers for them. This eliminates the need to use a different battery and “charger” for each individual device, and also makes it easier to find compatible power sources: instead of checking a list of compatible batteries, you just need to make sure that the battery you select is from a supported platform. (However, models of compatible batteries can also be specified in the specifications — see below for more details).

Batteries of the same platform mainly differ from each other in terms of capacity — and, accordingly, cost.

The operating voltage of the battery in the grinder with the appropriate power supply (see "Power supply"). The more powerful the tool, the higher the battery voltage, usually. At the same time, this parameter is usually selected in such a way as to optimally match the characteristics of a particular model; therefore, in fact, voltage data may be required only when looking for a spare or additional battery.

The capacity of the battery that is equipped with the tool with the appropriate type of power (see “Power source”).

Theoretically, the capacity directly determines how long the tool can work on one charge. However, in practice, this parameter is rather weakly related to real autonomy. Firstly, the charging time depends not only on the battery capacity, but also on the energy consumption (power) of the tool itself; secondly, the actual amount of stored energy is determined not only by the capacity in ampere hours, but also by the voltage in volts. So you can only compare tools with similar power and the same battery voltage in terms of battery capacity.

Note that some models of grinders allow replacing the “native” battery with another, including a higher capacity one; some manufacturers even produce universal batteries suitable for different types of power tools under a given brand.

Battery models that the device of the corresponding type is compatible with (see "Power source"). This information will be useful in cases where the battery(ies) must be purchased separately, for example, if the tool does not come with a battery at all, if you need to supplement the original package, or if the existing battery has failed.

The time required to fully (from zero to 100%) charge the battery in the battery device (see "Power supply"); this refers to the complete battery and standard charger. The shorter this time, the shorter the breaks will have to be done for recharging; however, higher capacity batteries inevitably take longer to charge than smaller ones. This can be compensated by the use of fast charging technologies, but they, in turn, affect the cost of the tool.

Approximate noise level generated by the grinder during operation. Note that this indicator is quite approximate, because. actual "loudness" can vary markedly depending on the type and shape of the material being processed, the surface it is placed on, and other circumstances. In addition, different manufacturers may use different measurement methods. Nevertheless, this indicator makes it possible to assess how comfortable this or that model is in operation and whether special hearing protection is required.

The most “quiet” modern grinders give out about 65 dB — this is comparable to loud speech at a distance of 1 m; in the loudest, the noise level reaches 107 dB — this is the volume of an industrial workshop.