Comparison NAC RLM800-DY vs NAC RLM800-NG

The highest angle of ascent or descent at which the mower maintains normal operation.

This parameter is indicated mainly for autonomous robotic mowers (see "Type") — it is for them that it is most relevant (in traditional models, everything depends mainly on whether the operator can keep the mower on the slope). In this case, the angle is indicated as a percentage, similar to how it is done on road signs: the number of percent corresponds to how many metres the terrain rises every 100 m of the road. For example, an angle of 25% means an ascent of 25 metres every 100 metres (or 25 cm every metre).

The most advanced modern robots are able to overcome slopes of 50% (that's about 30°) and even more. It is worth choosing according to this indicator, taking into account the characteristics of the area where the unit is planned to be operated: for example, for a flat lawn without ups and downs, you can not look at the permissible slope at all.

The ability to control the operation of a robotic lawn mower from a smartphone or tablet, and in some implementations, even from a computer. Communication can be established via a wireless Bluetooth channel or via a Wi-Fi network. Features of this control may vary depending on the model of lawn mower. So, in some instances you need to use a proprietary mobile application, for others it is enough to open a special page in an Internet browser. In any case, this function allows you to remotely access the control of the robotic lawn mower using mobile devices. And via a Wi-Fi network, control can be carried out from any corner of the globe where there is Internet coverage. This will come in handy when you are away from home - for example, on vacation or on a business trip.

Additional sensors included in the design of the robotic lawnmower (see "Type").

— Strike. A sensor that reacts to blows to the body of the device. It is mainly used for fixing collisions and avoiding obstacles: when a collision occurs and the sensor is triggered, the robot changes its direction of movement, trying to bypass the object that triggered the trigger. Such an opportunity will be especially useful for models without a mapping system (see "Functions"), however, it can also be useful if there is a built-in map: after all, in addition to permanent obstacles, other, temporary ones (for example, garden furniture taken out into the yard ). In addition, on some models, data from the collision sensor can be used to correct the built-in map.

— Tilt. A sensor that detects the tilt of the body in one direction or another. Mainly used to prevent rollover: when the angle of inclination reaches critical values, the mower reverses or otherwise changes the driving mode in an attempt to prevent the increase in inclination. This function will be especially useful when used in areas with relatively difficult terrain, with ups and downs.

— Rise. A sensor that reacts to the rise of the body above the ground — for example, if the device was picked up. With such a rise, the mower blades are open, which is fraught with injuries; the sensor prevents this; when it is triggered, the knives automatically stop. And in some models, this function also plays the role...of “anti-theft”: when the case is lifted, an alarm may turn on, warning the owner of an attempted theft.

— Overturning. A sensor that reacts to the flip of the body upside down. The main task of such a sensor is to stop the rotating knives so that they do not injure people who approach the mower (for example, curious children). And some models, when rolled over, can even send a message to the owner, warning him about the incident "state of emergency" and the inability to continue driving.

— Rain. A sensor that reacts to rain — more precisely, to the ingress of moisture on the body of the device, and sometimes to the presence of water under it. Robotic mowers themselves are made moisture resistant, and the main meaning of such a sensor is that lawns are usually not mowed in the rain: wet grass creates excessive resistance to the knives, they can become clogged with wet ground — as a result, the quality of the haircut noticeably deteriorates, and the mower experiences abnormal loads. Usually, when the sensor is triggered, the robot stops working and returns to the charging station.

— Obstacles. A sensor that detects the presence of obstacles in the path of the device. Unlike the shock sensor described above, which performs a similar function, this sensor usually works on a non-contact principle — for example, ultrasonic or infrared. This allows you to reduce to an absolute minimum the likelihood of collisions with various obstacles, which is especially important if there are delicate objects in the cultivated area — for example, fragile garden sculptures.

The maximum speed that the engine in an electric mower can run at (see "Engine type").

It makes sense to compare according to this indicator only engines of the same power. In general, higher rpm improves performance but reduces torque. Conversely, a relatively slow engine will be inferior to a “fast” one in overall speed, but it will better cope with dense dense vegetation. So it’s worth choosing by engine speed, taking into account what is more important to you — speed or efficiency in difficult conditions.

Nominal voltage of the battery used in the unit with the corresponding engine type (see above). Theoretically, a higher voltage allows you to achieve more power, but in fact there is no direct relationship between these points. In addition, manufacturers choose batteries to deliver the intended power, rotational speed, and other performance. Therefore, in the selection and normal use of the unit, this parameter has a secondary, reference value; it may be needed mainly for some specific tasks, for example, searching for a spare battery or a “non-native” charger, or comparing different batteries by capacity (see below).

Nominal capacity of the battery, nominally installed in the unit of the corresponding design (see "Engine type").

In general, the higher this indicator, the more energy the battery can store and the longer it can power the electric motor. At the same time, we recall that the actual battery life of the lawn mower will depend not only on the characteristics of the battery, but also on the power consumption of the unit — and this, in turn, is determined by the engine power, nozzle type, operating mode, grass density, etc. In addition , capacity is usually specified in ampere-hours; and the features of these units of measurement are such that only batteries with the same nominal voltage can be compared by them (see above).

Thus, the battery capacity when choosing is more of a reference and advertising parameter than practically significant, and only models with similar performance characteristics can be compared by it. To assess the actual battery life, it is better to pay attention to the operating time directly stated in the characteristics (see below).

The operating time of a battery-powered device (see "Motor type") on a single battery charge.

This indicator allows, to a certain extent, to assess the battery life of the unit. However note that the characteristics usually indicate the operating time under certain conditions, usually very favorable: low load on the nozzle, low and constant engine speed, etc. Therefore, in fact, battery life may differ from the claimed one — usually in a smaller direction, but vice versa is also possible. Nevertheless, according to the claimed operating time, it is quite possible to compare different models of cordless tools: the difference in official characteristics usually corresponds to the difference in actual battery life.

Time to fully (from 0 to 100%) charge the battery in the mower of the corresponding type (see "Engine type").

In general, a larger battery and takes longer to charge, but manufacturers can use various technologies that reduce charging time. So batteries of similar capacity can differ markedly in this indicator; of course, the faster option will cost more, but sometimes saving time is more important.

The level of noise produced by the device during operation. Usually, a certain average indicator is indicated in the characteristics — in the standard mode of operation; however, the actual values usually do not differ much from the claimed ones.

The lower the noise level, the more convenient the unit to use and the less tired the operator. In the case of lawn mowers, this is especially true, since such equipment is quite noisy — even the quietest models (some robots) give out about 47 – 48 dB, which is comparable to talking at an average volume. Note that the decibel is a non-linear quantity, and it is easiest to evaluate the actual loudness using comparative tables. Here is the simplest table for the values found in modern lawn mowers:

— 60 – 65 dB — talking in raised tones at a distance of about 1 m;
70 dB — loud conversation of several people at the same distance;
75 dB — loud laughter at a distance of 1 m;
80 dB — motorcycle engine, medium power vacuum cleaner.
90 dB — loud screams, freight car at a distance of 7 – 10 m;
100 dB — a subway train or a loud car signal at a distance of 5 – 7 m, an industrial workshop;
110 dB — tractor engine at a distance of about 1 m.

In addition to subjective sensations, there are specific sanitary standards that limit the impact of strong noise. So, according to European standards, noise of 85 dB is allowed to be heard without protective equipment for 8 hours, 91 dB — 2 hours, 97...dB — half an hour, and 103 dB — only 7 minutes. So when choosing a unit, you should take into account the duration of work with it — with high noise, you may need protective headphones.