Comparison Presto-Ps 7817 vs Karcher OS 5.320 S

The number of individual nozzles (nozzles) provided for in the design of the sprinkler. This number corresponds to the number of jets that the device is capable of delivering at the same time.

Theoretically, the more jets, the thinner they are and the more evenly the water is sprayed. However, in fact, this indicator by itself has practically no effect on irrigation efficiency: for example, a single nozzle of a properly selected design may not be inferior in efficiency to a set of several nozzles. Therefore, when choosing, it is worth focus not so much on the number of nozzles, but on other practical characteristics and features of the jet (the latter can be clarified, for example, from video reviews). We only note that oscillating sprinklers(see "Type"), by definition, are equipped with a set of several nozzles (up to 25 – 28).

The irrigation width provided by the sprinkler, to be more precise, the width of the area covered by the device at a time, without turning the nozzles horizontally.

This parameter is relevant primarily for oscillating models (see "Type") — they evenly capture a rectangular space, and the width is one of the main dimensions for a rectangle. In other types of sprinklers, we are talking about the width of the jet at maximum range (because the jet expands as it moves away from the nozzle); however, for such models, it is more convenient to indicate the size of the captured space by the angle of irrigation (see above), and the width for them is rarely indicated.

The maximum range that the sprinkler can provide.

The choice for this parameter depends primarily on the size of the area to be covered. However, keep in mind that a high range usually requires fairly high pressure and can degrade watering efficiency close to the nozzles. Therefore, even in large areas, it is sometimes more convenient to use a system of several sprinklers with a short range, rather than a long-range device.

The smallest area that a sprinkler can cover in normal operation, in other words, the area captured at a minimum range.

The minimum area is indicated only for models in which the size of the watered area can be adjusted (for example, by changing the angle). The smaller it is (at the same maximum), the wider the adjustment range. It also measures the suitability of a sprinkler for an area that is significantly smaller than the maximum irrigation area (see below). At the same time, when choosing, do not forget that models with the same area may differ in the shape of the space covered, the irrigation angle, etc.

The largest area that the sprinkler can cover during operation (or the standard coverage area for models that do not allow changing the size of the captured area).

The larger the area, the more watering area it may require. At the same time, the irrigation system must correspond not only to the area, but also to the shape of the site. Therefore, a model covering a large area is not always the best choice — sometimes (especially in areas of complex shape) it is easier to cover the required space with a few relatively modest sprinklers.

In some cases, knowing the irrigation area, you can determine other characteristics of the device: for example, for a sprinkler with an irrigation angle of 360 °, you can calculate the maximum range without much difficulty, even if it is not indicated in the characteristics.

The pressure of the water in the connected hose/pipe that the sprinkler is designed to handle: lower pressure will not give the device the required performance, higher pressure may cause damage. And even if too high pressure did not lead to an "accident" immediately, it can happen at any time. Therefore, this parameter should never be ignored.

The best option is considered to be the situation when the pressure in the hose is slightly (by 0.4 — 0.5 bar) does not reach the claimed maximum — this allows you to fully realize all the capabilities of the sprinkler and at the same time gives a guarantee against breakage in case of pressure surges.

The main material used in the construction of the sprinkler.

— Plastic. The key advantages of plastic are its low cost and ease of processing, making it well suited for complex shaped parts. In addition, this material is lightweight and completely corrosion resistant. On the other hand, plastic is less durable and reliable than metal, and is less suitable for rubbing and other parts in contact with each other. However, in the case of sprinklers, this moment is not critical, and most modern models are made of plastic.

— Metal. Metal favorably differs from plastic in higher strength and, theoretically, durability. On the other hand, it weighs more and is much more expensive; in addition, water-resistant alloys and/or coatings must be used in sprinklers, which further increases the cost. Therefore, this material is used relatively rarely — mainly in fairly advanced models of the impulse type(see above).

— Metal / plastic. A combination of the two materials described above: usually, the most critical elements are made of metal, while the rest of the device uses plastic. This design allows you to combine the advantages of both materials and partially compensate for their shortcomings: metal-plastic sprinklers are not as expensive and heavy as all-metal ones, and at the same time more durable and reliable than plastic ones. This option is very popul...ar, especially in models of the middle and upper classes.