Comparison Volks 4SKm150 vs Rudes 4S 1.1-50-0.5

The maximum amount of water that the pump can deliver from the well per unit of time. The choice for this parameter depends on two main points: the maximum total consumption and productivity of the well.

The maximum total consumption is the amount of water that is necessary for the simultaneous normal operation of all points of water intake in the system. Different types of consumers (washbasins, showers, washing machines, etc.) require different amounts of water; exact values can be found in special tables or instructions for specific models of household appliances. And the total consumption can be calculated by adding the indicators of all points of water intake. As for the productivity of the well, this is the maximum amount of water that the well can produce in a certain time without draining it. This indicator is usually indicated in the documents for the well; if it is unknown, before buying a permanent pump, it is imperative to determine the productivity — for example, by trial pumping with an inexpensive unit.

Accordingly, the performance of the pump should not exceed the productivity of the well, and it should be at least 50% of the maximum total consumption of the connected water supply system. The first rule allows you to avoid draining the pump and the troubles associated with it, and compliance with the second guarantees a normal amount of water even with a rather intensive water intake. And, of course, do not forget that high performance requires high power and affects the cost of the device.

The highest pressure that can occur in the line when the pump is running. Note that usually we are not talking about normal working pressure (it is described by max. head, see above), but about short-term jumps that can significantly exceed standard values. The water supply system to which the pump is connected must normally tolerate not only standard values but also the mentioned jumps — otherwise, an accident may occur. Accordingly, the maximum working pressure is useful for assessing how the safety factor of pipes, fittings and other elements of the system corresponds to the characteristics of the pump.

The basic principle or principles by which the suction action of the pump is carried out.

— Centrifugal. As the name suggests, this type of pump uses centrifugal force. Their main element is the impeller installed in a round casing; the inlet is located on the axis of rotation of this wheel. During operation, due to the centrifugal force that occurs during the rotation of the wheel, the liquid is thrown from the centre to its edges and then enters the outlet pipe directed tangentially to the circle of rotation of the wheel. Centrifugal pumps are quite simple in design and inexpensive, while they are reliable and economical (due to high efficiency), and the fluid flow is continuous. At the same time, the performance of such units can drop significantly with high resistance in the water supply system, and the resistance to pollution, although higher than that of vortex units, is still noticeably inferior to auger ones(see below).

— Vortex. Vortex pumps are somewhat similar to centrifugal pumps: they also have a round casing and an impeller with blades. However, in such units, both the inlet and outlet pipes are directed tangentially to the impeller, and the blades differ in design. The method of operation is also fundamentally different — by the name, of it uses the vortices formed on the wheel blades. Vortex units are significantly superior to centrifug...al units in terms of pressure but they are more sensitive to contamination — even small particles entering the impeller can cause damage, significantly reducing efficiency. In addition, the efficiency of such pumps is low — 2-3 times lower than that of centrifugal ones.

— Auger. The main part of such pumps is a rotor in the form of an auger (or several such rotors). The main advantage of pumps of this type is high reliability — they can easily cope even with very sandy water; in addition, the level of noise and vibration during operation is minimal. On the other hand, auger pumps are inferior to the options described above in terms of performance, and their cost is quite high due to the requirements for production quality.

The greatest depth under water at which the pump is capable of operating normally.

The optimal location for the deep well pump is as close to the bottom as possible (no closer than 1 m, but this margin can be ignored in this case). It is worth choosing according to the maximum depth, taking into account the depth of the well and the static water level in it (the distance at which the water mirror is located from the surface of the earth when the pump is turned off). For example, there is a well 50 m deep with a static level of 20 m; thus, the depth to the bottom is 50 – 20 = 30 m, and if you want to lower the pump to the very bottom, the maximum immersion depth must be at least 30 m — otherwise too high water pressure may damage the unit.

The largest amount of mechanical impurities in the pumped water, which the pump can handle normally. When used with dirty water, this parameter should be taken into account along with the maximum particle size (see above): if the impurity content is too high, the pump may fail even if the individual particle size does not exceed the norm.

The pH value of the pumped liquid for which the pump is designed. This indicator describes the level of acidity of the medium, roughly speaking, how reactive it is to the “acidic” or “alkaline” side: low pH values correspond to an acidic environment, and high pH values are alkaline. Acid and alkaline have different effects on the materials used in the design of various equipment, including pumps. Therefore, when designing parts in direct contact with water, the pH level must be taken into account, and using the pump with unsuitable water is not recommended — this can lead to corrosion, poor water quality and a quick failure of the unit. At the same time, it is worth noting that drinking water wells typically have a pH of 6.5 to 8, and overlapping this range (and even wider) is not a problem. Therefore, this parameter can be called secondary, and in many models, it is not indicated at all.

The power consumed by the pump motor during operation. A more powerful engine can provide more head and performance, but these parameters are not directly related: two models of similar power can differ markedly in practical characteristics. Therefore, this parameter is secondary, and more or less unambiguously it describes only the class of the unit as a whole — powerful engines are typical for high-end performant models. But what this characteristic directly affects is the actual power consumption; and with it, in turn, are connected not only to electricity bills but also connection requirements.

The length of the standard power cable provided in the design of the pump.

Ideally, the length of this cable should not be less than the maximum immersion depth — this will ensure maximum ease of connection: the connection point of the cable to the mains will be above the water (in the best case, even outside the well), and you will not have to worry about insulation. At the same time, for several reasons, many pumps are equipped with rather short cords — about 1.5-2 m, and not long cables; in such cases, it is necessary to use special waterproof equipment.

A safety system in case of an overload of a deep well pump when its engine is running beyond its capacity. It can lead to engine failure or even fire. Overloading is usually prevented by thermal current relays introduced into the circuit of pumping equipment.