Comparison Zipper ZI-GHAS2800 vs Ryobi RSH2545B

Type of materials for which the shredder was originally designed.

— Leaves only. In this case, we mean shredders designed for all types of “soft” and wet garden waste: leaves themselves, thick stems of herbaceous plants, freshly cut branches of small thickness, etc. Typically, these models use a knife or line chopping system (see below). Many units for this purpose can cope with coarser dry waste, but this mode of operation is still not recommended, because. it increases the wear of cutting elements, leading to rapid blunting and failure.

— Branches only. Shredders designed to work with coarse materials — primarily large dry branches with a thickness of several tens of millimetres (for more details, see "Maximum diameter of shredded material"). Usually, roller chopping systems are used for such work (see below). Aggregates of this type without much difficulty "eat" and medium-sized soft debris, however, the quality of its processing is much lower than in specialized models for leaves. Therefore, it hardly makes sense to use this type of shredders for "non-native" material.

— Branches and leaves. Models that process both types of garbage described above with equal efficiency — both soft (leaves, freshly cut thin branches) and hard (dry thick branches). Some models have separate modes of operation for both, while others have separate holes for hard...and soft materials (see Features). Anyway, such shredders are the most versatile, however, their cost is higher than that of specialized ones.

The design of the tool used to grind the garbage entering the unit.

— Knife. The main element of such systems, as the name implies, are special knives. Their design can be different: triangular blades with sharpening, rotating discs with several blades, etc. Anyway, this option is considered optimal for working with leaves, because. it ensures thorough and uniform processing of such waste. But with solid large branches, knife systems are less compatible; see "Crushing" for details.

— Valkovaya. Also, such systems are called milling. Their action is based on the use of gears with large teeth, which, when rotated, “bite off” and crush pieces of the processed material. This allows you to effectively process thick dry branches, besides, the gears themselves draw the debris inside, in fact, providing automatic feeding (see below). But roll systems do not work well with leaves and other “soft” debris. Therefore, models of this design are usually intended purely for branches (see "Chipping").

— Turbine. Turbine systems use a cutting element in the form of a cylindrical or conical drum with blades located horizontally. Their design is such that the shredder is able to cope equally effectively with both leaves and thick branches (see "Chipping"). The main disadvantage of "turbines" is the high cost.

— Leskovaya. As the name implies, systems of t...his type use a fishing line that rotates at high speed during operation. They are designed to work exclusively with leaves (see "Crushing"), and it is the leaves that the scaffold unit processes in the best quality. But with other types of garbage — even with thick grassy stems — such shredders can have problems.

The largest thickness of debris that the shredder can handle normally. This parameter will allow you to evaluate how a particular device is suitable for a particular situation.

Note that the maximum diameter of the crushed material is important for models that allow working with branches (see "Chipping"). But in specialized aggregates for leaves, it is usually not indicated at all: the thickness of the garbage processed in such grinders is, by definition, small, and creating a design that works normally with any “soft” materials is usually not a problem.

The speed of rotation of the cutting tool of the chopper (see "Crushing system"). Variable speed models (see below) usually have a maximum RPM value.

In general, the general pattern is as follows: with equal engine power, the higher the speed, the lower the torque (see below), and vice versa. In addition, high speed improves performance (see "Bandwidth"). At the same time, this parameter in most cases is more of a reference value than a practically significant one: manufacturers select the rotation speed in such a way that it provides the claimed throughput and at the same time maintains the torque at a sufficient level for efficient processing of materials that were originally calculated design. Therefore, in some models, revolutions may not be indicated at all, and when choosing, it is worth focus on moments that are closer to practice.

The capacity of the garbage collector provided in the design or delivery set of the grinder.

The larger the container, the more recycled material the collector can hold and the less often it will have to be emptied. On the other hand, it is not always convenient to carry a large amount of material, and a large container takes up a lot of space — and if for soft bags (see "Type of collection") the latter is relevant only when fully loaded, then rigid containers are bulky by definition. Therefore, when choosing, you should proceed from the optimal compromise between capacity and convenience.

— Auto feed. Autofeed refers to all systems that somehow ensure the "pulling" of debris into the working mechanism of the unit. Roller chopping systems (see above) by definition have this feature; in other types of shredders, additional mechanisms may be provided specifically for automatic feeding.

— Pusher. The presence of a pusher in the design or delivery set of the unit. The pusher is a device that allows you to manually push the garbage to the working mechanism of the grinder; such devices are specially adapted to the shape and design of the receiving chamber, therefore, when used, they are more efficient and at the same time safer than various improvised means. The pusher can be useful both in the absence of automatic feed and in its presence (see above): it happens that debris gets stuck “on the way” to the tightening mechanism, which requires additional measures from the operator.

— Dual chamber receiver. The presence in the design of the chopper of the receiver, which has two separate chambers. Each of these chambers is designed for its own type of garbage; at the same time, the chopper itself can be both universal and specialized, for branches (see "Chopping"). In the first case, different chambers are designed for different types of debris, in the second — for branches of different thicknesses. Anyway, the dual-chamber receiver simplifies the wo...rk with the universal unit — it reduces the risk of confusing modes for different materials.

— Funnel for foliage. The presence of a special funnel for collecting foliage in the chopper design. Such a funnel usually has the form of a characteristic wide bell, mounted on a swivel mount and laid on the ground during use. In such a socket, as in a scoop, you can sweep the leaves collected with a rake or broom — it's easier and faster than loading them into the chopper with your hands.

— Reverse system. The presence of a reverse function in the chopper design. This function allows you to run the working nozzle in the opposite direction, and its use may vary depending on the chopper model. So, in models with roller shredding systems (see above), the reverse allows you to “spit out” a branch that is too thick or hard and release the jammed mechanism, and in some universal devices (see “Chipping”), by switching the direction, you can choose between modes for different types of debris .

The operating power of the chopper motor, expressed in watts. This designation is used for all electric models (see "Engine type"), but can also be used for gasoline / diesel.

The performance of the unit and its ability to cope with hard and thick branches primarily depend on the engine power. In general, the more powerful the grinder, the more advanced it is considered. However, it should be taken into account here that these moments are also highly dependent on other design features — the specifics of a particular motor, grinding system (see above), etc. Therefore, when choosing, it makes sense to pay attention first of all to the direct performance characteristics, such as the type of material being processed (see "Grinding"), its thickness (see "Maximum diameter of the material being ground"), etc. And the power itself can be useful for a general assessment of a particular model. So, shredders up to 1.5 kW inclusive belong mainly to the entry level, the middle class can carry an engine up to 2.5 kW, and higher rates are typical for professional units. Detailed recommendations on the optimal power for a particular situation can be found in special sources.

Availability of protection against an overload in a design of a grinder.

Overload is a critical increase in the load on the working mechanism and, accordingly, the engine of the device. Such a situation may arise, for example, when too large or solid debris (or too many “regular” materials) enters the unit; at best, its consequences are limited to increased wear, at worst, an accident can occur. The protection system prevents such troubles by shutting down the motor (or the drive to the grinding system) in the event of an overload. Of course, you can also turn off the unit manually — however, automation is more reliable, since it constantly monitors the status of the device and reacts almost instantly.

The maximum noise level produced by the grinder during normal operation. The comfort of using the unit primarily depends on this indicator: strong noise can be very unpleasant, and at high volume it may even require the use of protective headphones.

Shredders are a rather “loud” type of modern technology, even in the quietest models the noise level is about 83 – 85 dB — this is comparable to the sound background on a busy city street. Note that the decibel is a non-linear quantity, so it is best to use comparison tables to estimate specific noise levels. Here are some guideline values:

• 90 dB — freight car at a distance of 7 – 10 m;
• 95 dB — subway car (inside), perforator;
• 100 dB — symphony orchestra, demolition hammer;
• 105 dB — home theater at maximum volume;
• 110 dB — indoor rock concert.