Frequency electronic converters for electric pumps of water supply systems. Frequency converter for well pump Frequency converter for single-phase pump

Pumps are needed to regulate the power of engines. As a result, the pressure in the system is maintained at the proper level. High-quality converters can save money a large number of electricity. And this should be taken into account. In this case, a wide variety of pumps can be used. The most common are systems for supplying water to the house. Converters are also needed for circulation pumps. Additionally, they can be installed in fountains and aquariums.

Features of converters

The hallmark of all pump converters is their simplicity. However, they do not require any maintenance and operate completely automatically. Additionally, it is possible to control them via a personal computer. You can also set individual operating schedules for the device. In this case, the coefficient useful action theirs is about 90%. You should also know that pumps with converters do not need expansion tank. Thus, the pressure is always maintained at the optimal level.

What characteristics do converters have?

The important characteristics of converters are the input voltage and power. Additionally, the manufacturer always indicates the type of control. Today, a distinction is made between scalar and vector control of the device. The rated current parameter depends on the power of the model. You can also highlight the output frequency indicator. It is usually specified in the range from 0.1 to 600 Hz. Overload capacity is calculated as a percentage. The degree of protection of the converter housing is indicated by special markings. Working temperature The manufacturer of the device must also indicate it. Among other things, the acceleration and deceleration time parameters should be highlighted.

Reviews of Danfoss 2800 converters

The Danfoss frequency converter is quite easy to maintain and operate. In this case, dense installation of equipment is allowed. This is largely due to the reliable cooling system. To monitor the pressure level, the device has special sensors. Separately, it is worth mentioning a high-quality PID controller. The input is 220 V, and the power is 0.2 kW.

The output frequency ranges from 0.1 to 600 Hz. The frequency converter is controlled in a vector manner. The complete acceleration time takes an average of 30 seconds. The degree of protection of the housing is class "IP20". The dimensions of this unit are as follows: height - 174 mm, width - 73 mm, and depth - 135 mm. The Danfoss 2800 frequency converter costs approximately 11 thousand rubles.

Model INVT GD10: characteristics and reviews

Many buyers have appreciated these frequency converters for pumps for their large number of discrete inputs. Among other things, the presence of a relay output should be highlighted. This converter can be used at temperatures from -10 to +50 degrees. The manufacturer provides a built-in PID controller.

Also, many praised the multifunctional keyboard. With its help you can quickly access absolutely all parameters. Input voltage of this device The rated power of the motor is 0.2 kW, and the frequency ranges from 0 to 400 Hz. The rated current parameter is 1.6 A. The degree of protection of the housing is class "IP20". The overload capacity of this converter is 150%. This model will cost the buyer 12 thousand rubles.

Converter "Vesper E3-8100"

The Vesper E3-8100 frequency converter can boast of its modest size. Among other things, it has special communication adapters that are designed for the network. Also worth noting is the convenient optional remote control. It is equipped with modern software. Printed circuit boards protection devices are varnished.

The manufacturer allows dense installation of devices. The control type in this converter is vector. The rated power of the device is 0.75 kW, and the output voltage is 22 V. The output frequency of the device fluctuates around 200 Hz. The total acceleration time is 30 seconds, and the total braking time is 50 seconds. The degree of protection of the housing is set to class "IP20". The unit can be operated at temperatures from -10 to +50 degrees. The Vesper E3-8100 frequency converter costs 13 thousand rubles.

INVT GD15 converter parameters

Voltage regulation in this converter occurs automatically. There are a total of five discrete inputs. The PID controller is installed as a built-in type. The manufacturer also provides support for all standard programs. The keyboard is multifunctional and provides quick access to the system. Separately, it is worth mentioning the EMC filter, which is built into the housing. The single phase converter control is of scalar type.

The input voltage of the device ranges from 205 to 235 V, and the motor power is 0.4 kW. The output frequency is at around 300 Hz. In turn, the rated current is 2.5 A. For 10 seconds. the overload capacity of the converter is 180%. The dimensions of this model are as follows: height - 140 mm, width - 80 mm, and depth - 134 mm. This device will cost the buyer 14 thousand rubles.

Reviews of the INVT GD20 model

These frequency converters for pumps are in great demand and have good system protection. Analog inputs and outputs are provided by the manufacturer. Also worth noting is the built-in C485 port with support for many standard programs. The brake module is installed as a built-in type. The EMC filter is class C2. The converter protection system copes quite successfully with various kinds interference.

If necessary, the remote control in the device can be easily disconnected. The dimensions of the converter are quite compact and its weight is only 1.5 kg. The rated power of the unit is 0.7 kW, and the frequency fluctuates around 200 Hz. The rated current parameter is 4.2 A. The device can be used at temperatures from -10 to +40 degrees. Separately, it is worth mentioning the good overload capacity. The control type, in turn, is of a scalar type. This frequency converter costs (market price) approximately 12 thousand rubles.

Customers' opinions about the Hyundai 700E device

This Hyundai frequency converter differs from other devices in its high-quality PID controller. In this case, the braking module is installed as a built-in type. The control panel is quite user-friendly and is equipped with a potentiometer to control the rotation speed. This model is suitable not only for pumps, but also for fans. Among other things, it is often installed on various conveyors. The EMC filter is of the built-in type.

Drives for this model come from different manufacturers, and this is very convenient. The device is quite easy to install and easy to maintain. For commissioning, you can use "Flashdrop". The control type in this model is classified as scalar. The input voltage of the device ranges from 200 to 240 V. At the same time, the operating power single phase motor is 0.37 kW. Special mention should be made of the wide range of output frequencies. The rated current is 2.4 A, and the overload capacity is 150%. The degree of protection in the converter is set to IP20 class. The height of this unit is 202 mm, width - 75 mm, and depth - 142 mm, with a weight of 1.1 kg. The Hyundai 700E frequency converter costs 12 thousand rubles in a specialized store.

Characteristics of the Schnyder AT12 converter

Connecting the Schnyder AT12 frequency converter to circulation pumps is quite simple. This model differs from other devices in its compactness and increased performance. Among other things, the multifunctionality of the device should be noted. Manufacturers additionally paid great attention to the security system.

The overload capacity parameter remains 150%. The motor is single-phase, with a power of 0.18 kW. In this case, the rated current parameter is 1.4 A. The total acceleration time takes 20 seconds, and the braking time takes 55 seconds. The average output frequency is around 250 Hz. In this case, the maximum it can rise to 400 Hz. In turn, the input voltage of the converter is 220 V. This model costs 14 thousand rubles in the store.

Model "Lovara N3"

Frequency converters for Lovar N3 pumps have acceptable characteristics, but have one drawback. It is associated with the formation of condensation. This largely depends on unprotected contacts. The possibility of synchronous operation is provided in this model. It is also worth noting the versatility of the device. Starting and stopping the engine can be done remotely. Current signals are received from 4 to 20 mA.

Temperature environment should be from 5 to 40 degrees. Depending on the pressure in the system, the engine speed is controlled automatically. The input voltage indicator is at the level of 400 V. The rated power of the three-phase motor is 3 kW. This model will cost the buyer 15 thousand rubles.

Converter FC-051

The FC-051 frequency converter is actively used for pumps and ventilation systems. This model is distinguished by a high-quality control unit. It should be noted that the device interface is good. You can connect this converter to a personal computer. The mechanical seal is locked automatically.

If necessary, the remote control can be easily detached. In this case, the device can be started remotely from any distance. If the pressure increases, the protective system immediately activates and blocks the engine. It also protects the system from various power surges. The indication in this model is LED. At the same time, the control panel contains only the most necessary indicators. The noise level of the electric motor is within normal limits. This was largely achieved due to a high-quality variator, which produces a stable frequency at 8 kHz.

To cool the entire converter there is powerful fan. It is installed at the base of the frame and securely fastened. In this case, the device can be used for a long time and not overheat. Additionally, it should be noted that the tracking system constantly monitors external pressure. On centrifugal pumps This model can be installed. The control sensor can withstand a maximum output signal of up to 20 mA. This frequency converter costs (market price) approximately 16 thousand rubles.

Any equipment needed for efficient work water pump and what is not included in its standard package is called additional. As a rule, the standard equipment of a pumping station includes the following components: a submersible or surface pump, a pressure gauge, a stainless steel hose, a hydraulic accumulator, and a water pressure switch. Additional equipment includes auxiliary products such as a frequency converter for well pump, voltage stabilizers, source uninterruptible power supply(UPS), its second name is a voltage converter, various sensors, blocks, control relays and much more. In our article we will look at the purpose and features of using the main additional equipment for pumps.

For any pumping station, protection against dry operation is very important. This can happen in conditions of water shortage at the source. If the water intake is completely empty, the unit will operate “dry”. This will lead to overheating of the impeller (impeller) and other important elements of the working chamber. As a result of thermal deformation, parts may jam and the unit will fail. To prevent this from happening, you will need a block that protects the unit from dry running. These blocks include various parts:

• electronic controllers;
• float mechanism;
• electromechanical regulator (relay).

Let's look at the features of the device and the use of some of them.

Simple controller

The electronic relay has a flow sensor, which allows you to determine the presence or absence of water flow in the pipes. If the regulator indicates that there is no water in the pipeline, the device turns off the pumping equipment. There are many types of controllers on sale, differing in functionality and appearance. The simplest of them are equipped only with a flow sensor. The most advanced models can combine the functions of limit pressure control to turn the unit on and off, as well as protection against dry operation.

For a standard pumping station with electromechanical pressure control, it is enough to buy a simple electronic controller. Such a block will protect the unit from dry running. It is installed on the supply pipeline.

If you use a pumping station without a hydraulic accumulator, then you will also need a control unit that protects against dry operation. This device will ensure that pumping equipment stops when water consumption points are closed. The flow sensor will also work in this case, because the flow of water will stop when the flow from the pipeline stops.

Controller with additional options

Such an improved controller for pumping equipment can:

• control the pressure using the built-in pressure gauge;
• the device may attempt to automatically restart the pump after a certain period of time;
• set the lower pressure threshold to turn on the unit;
• control the upper and lower pressure thresholds (these are universal units that combine a pressure regulator and a flow sensor).

It is important to know: in some modifications of new controllers, the user can independently change the upper and lower pressure thresholds within specified limits.

Electromechanical devices for protection against dry operation

Electromechanical control devices are designated by the letters LP3. They also protect the unit from dry running. At their core, they are the same pressure switches. However, there are slight differences:

• such a unit works only with low pressure;
• this device turns off the pump when the lower pressure limit is reached, and turns it on when the upper limit is reached, while conventional relays do the opposite;
• the device is practically insensitive to voltage surges;
• its reliability and durability are much higher;
• the price of this unit is lower compared to the cost of a conventional relay;
• If the pump stops due to dry running protection, the control unit will not restart the pump; the user will have to do this manually.

Float mechanism

This device consists of a float, inside of which there is a steel ball, and an electrical cable. When water is drawn into the device, the float block floats up. At this time, the ball is in a position where it closes electrical circuit. This leads to the startup and operation of the pumping equipment. If the float block drops due to a decrease in the water level, the ball changes its position and opens the circuit, which leads to the device turning off.

Surge Protectors

Attention: when starting pumping equipment, the already low voltage in the suburban network may drop to a minimum, which will lead to failure of household electrical appliances. The thing is that in such conditions the devices will operate at maximum power to compensate for the missing voltage.

In addition, a lack of voltage will negatively affect the motor of the pumping equipment, as well as the ability of the unit to provide sufficient water pressure. To prevent this from happening, you need to purchase a voltage stabilizer for units pumping water.

To choose the right stabilizer, you need to consider the following nuances:

1. You need to know the magnitude of the starting currents. It can be obtained from the manufacturer or calculated using the formula. First, we determine the operating current by dividing the engine power by the voltage (220 V) and multiplying by a power factor equal to 0.6-0.8. After this, we multiply the learned number by 4 and get the desired value.
2. The voltage stabilizer must have a power that allows you to connect not only pumping equipment to it.
3. Choose a stabilizer whose model is adapted to work with units equipped with an electric motor. Relay type stabilizers, which have an increased stabilization speed, are ideally suited for these needs.
4. Three-phase stabilizers with increased power are suitable for three-phase pumps.
5. As a rule, a stabilizer for a pump must be selected with three times the power.
6. The lower the input voltage, the greater the power reserve you need to give to the stabilizer.
7. During operation, it is better to load the device at 80%, and not at 100%. This will increase the service life of the device.

Types of stabilizing devices:

• thyristor;
• relay;
• electromechanical.

The choice of one or another type of stabilizer depends on the voltage level in the network, the distance at which the object is installed from transformer substation, voltage surge on this line. If there are no sharp surges and high voltage readings, you can choose an electromechanical device that has smooth adjustment. For lines with network surges, relay or thyristor models are suitable.

Frequency converter for pump

Various devices are used to control pumping equipment:

1. An alarm relay is required to switch off a running pump due to changes in operating mode.
2. In order to switch circuits in the required sequence, an intermediate relay is needed.
3. As we already wrote above, to protect against power surges you will need a voltage relay.
4. To count the time for performing a certain operation, a timer is needed.
5. To monitor pressure in the pipeline and control automatic circuits, an electric contact pressure gauge is useful.
6. To measure the temperature of bearings and seals, you need a thermostat.
7. Level sensors provide a signal to start or stop the unit due to changes in pressure or liquid level.
8. The vacuum relay maintains a given level of vacuum in the device chamber or in the inlet pipeline.
9. A jet relay is used to control the movement of liquid in pipes.

Important: The frequency converter is especially important in systems with multiple pumps.

Advantages of using a frequency converter to control a pump:

• The engine starts smoothly. This helps reduce the impact of mechanical loads on pumping equipment. In addition, reducing starting currents reduces the risk of water hammer. The absence of water hammer has a beneficial effect on the durability and integrity of the entire hydraulic structure.
• Thanks to this, the resource of the pumping unit is consumed more economically. This will extend the service life of the equipment.
• Using a frequency converter helps save energy.

The disadvantages of a frequency converter for controlling pumping equipment include the following:

• High price of the device. Not even for purchasing pumps high power The cost of such a converter will be quite high.
• The pump control converter can only be used if the cable length is no more than 50 m.

Uninterruptible power supplies

To ensure constant power supply to pumping equipment, special uninterruptible power supplies (UPS), also known as voltage converters, are used. The operating principle of this device is based on the fact that when there is current in the electrical network, it charges special batteries. When there is a power outage, the unit consumes electricity from the batteries. At the same time, it transforms D.C.(12 V), producing alternating (220 V).

In other words, if only additional devices are needed to control the pump, then the converter ensures its uninterrupted operation in the event of a power outage. This device connects to rechargeable batteries and connects to the electrical network.

A frequency sine wave in uninterruptible power supplies for pumping equipment is necessary, since without it the units will make a lot of noise and overheat. As a result, the thin winding may simply burn out. Typically, the UPS power is 1000-2000 W. This power is enough not only to ensure the operation of pumping equipment, but also to maintain the operation of heating boilers, TV and lighting throughout the house.

In our article, we examined the most necessary additional equipment that is needed to facilitate pump control, increase its efficiency, and protect against failure if operating conditions change.

1. Pressure stabilization. The emergency control system maintains pressure at the right level(the value is set by the user) regardless of the time of day, the number of open taps and the configuration of the main line. This also has a number of advantages: with hot water supply using flow-through, the temperature of the liquid remains unchanged; household appliances connected to the water supply operate in optimal mode.
2. Protection of the pump from overheating. The frequency converter includes a flow relay. Consequently, the pumping device is protected from dry running.
3. Smooth start. It eliminates overloads when voltage is supplied to the electric motor.
4. Optimization of electricity consumption. Since the pump is constantly switched from one mode to another, energy consumption becomes more economical. If the pumping device is of high power, the reduction reaches 50%. According to some estimates, this alone will pay for the frequency converter in about 1.5 years.
5. Reducing the risk of leaks (breaks in the main line). The explanation is simple - the pressure is maintained within normal limits, and therefore emergency situations excluded due to its jumps. It turns out that the frequency converter indirectly saves on materials and time required to troubleshoot problems in the system. Consequently, the associated excess water consumption (penetration into the ground, spreading across the floor ground floor) will not be.
6. Increasing pump life. The frequency converter regulates the current and voltage (0 - 230 V), and the absence of sudden jumps extends the service life of the pumping device.
7. Remote control. Some models of emergency situations have a USB (COM) port, and you can change settings from a PC; additional convenience for the user.
8. Emergency pump shutdown. Therefore, one of the functions of a frequency converter is protective.
9. There is no need to include a hydraulic accumulator in the circuit. When the pump and emergency operation work together, it is simply not needed.

Automation of pumping equipment can be considered the most important aspect in the field of technical development of water supply and wastewater systems. This is important not only for stations that provide water to populated areas.

A smart well pump will also make operation comfortable autonomous water supply. To do this, it is very important to correctly calculate the well pump, and, according to the calculations obtained, select a frequency converter for it.

The video in this article will help you do it yourself.

Advantages of automatic water supply

To achieve the most gentle operation of equipment, pumping stations automate everything - from starting and stopping units to controlling water flow. Devices that help to exercise total control over the system transmit signals to the display in the control room.

About the same thing, only on a smaller scale, happens in the case of automation. home pump. Let's look at what advantages automation gives the system.

So:

• The most important thing is this: smooth starting and stopping of the pump motor reduces the likelihood of water hammer to zero, and careful operation helps to extend the service life of any equipment. At the same time, the costs associated with the operation of the water intake are reduced.
• First of all, this is energy consumption. Its price is steadily rising, and everyone feels it: both individuals and enterprises. Frequency control of pump motors makes it possible to reduce the volume of storage tanks, and even eliminate them completely.

In such cases, they use a device called an “inverter control unit for a well pump” - this is what you see in the photo above. The inverter combines various combinations of control devices that the pump itself is not equipped with, including a built-in frequency converter.

Functionality and selection of frequency converter

It is clear that maximum water consumption occurs only at certain moments, and most time the pump power becomes excessive. The frequency converter allows you to configure the system so that during rush hour the pump delivers full power, and the rest of the time it reduces speed.

• The pressure it develops and, accordingly, its performance depends on the number of rotations of the pump wheel in a certain period of time. The essence of using a frequency converter is to make the motor shaft rotate at a given pace. In this case, the frequency alternating current, received from the electrical network, changes its value.
• Modern converters have a wide range and are capable of converting voltages both above and below the characteristics of the supply network. The circuit of this device is divided into two parts: the power part, consisting of a group of transistors or thyristors, and the control part, which is essentially an electronic switch.
• The control part consists of digital microprocessors and performs all control and protective functions. Since the structure of the power part has characteristic differences, frequency converters are divided into two groups. One of them includes devices with an intermediate DC link.

• The second group does not have this link and is called “frequency converters with direct coupling.” Devices without an intermediate link have higher efficiency and are able to “curb” the most powerful high-voltage motor. Despite the fact that the price this option higher, the system in which it is implemented is an order of magnitude more economical in terms of costs.
• What are the savings due to? The fact is that such converters have a small frequency range, and it cannot be equal to or exceed the characteristics of the supply network. The standard frequency of the current in the network is 50Hz, and the device converts it to 30Hz and below, down to zero. Consequently, energy consumption is reduced - that's savings for you!

Such a limited range does not allow the use of converters of this type on an industrial scale. But for household pumps this is exactly what you need.

Selection of pump for a well

First of all, you need to keep in mind that the power characteristics of the pump must exceed the calculated consumption. That is, there should always be a reserve of power.

The calculation is based on the following data:

• Depth and
• Casing diameter
• , or, to put it simply, the distance from the water surface in the well to the surface of the earth when the pump is running
• Total daily water consumption for a family, keeping animals and watering (calculated based on existing standards)
• Distance of the well from the house
• Water supply height (taking into account the number of floors of the building)
• Pressure pipe diameter

The pump pressure for the well, from which water will be supplied directly to the house, is the sum of the length of the vertical and horizontal distances multiplied by the resistance of the pipeline - this coefficient is a constant value and is equal to 1.15.

• If there is a storage tank in the water supply system, then the pressure of the hydraulic tank is also added to the sum of the distances. Pressure is expressed in atmospheres, and each atmosphere is equivalent to 10 vertical meters.
• Let's see what the calculation will look like specific example. Let's say you have a well with a dynamic level of 35 m. It is located 20 m from two-story house 7 m high. At the same time, a hydraulic accumulator with a capacity of 60 liters and a pressure of 3 atm is installed in the house.

The pressure calculation will look like this: H = (35+20+7+(3*10))*1.15 = 105 meters.

If you take into account a small reserve, you can buy a pump with a pressure characteristic of 110-115m. As you can see, this calculation is not particularly difficult. Now let's talk about the criteria for selecting a frequency converter, abbreviated as FC.

Converter selection

As for the technical characteristics of the state of emergency, they must be correlated with the type and power of the electric motor to which it will be connected. Next, you need to take into account the required range of regulation, as well as the level of accuracy of adjustment and maintenance of torque on the motor shaft.

• The design features of the inverter, that is, its dimensions, configuration, built-in or remote control, also matter. The vast majority are installed asynchronous motors. The emergency response is selected for them based on power, and it is better if this characteristic of the converter is an order of magnitude higher than that of the pump.

• There are converters with vector control that allow you to maintain the rotation speed under variable loads, as well as work without reducing the speed in the zero range. Such converters most accurately control torque and shaft speed. This is especially important when there are two pumps in the network.
• In general, frequency converters have their own classification. Like any other electrical equipment, they can be single-phase or three-phase. The inverter version can be domestic, for a 220V network. There are also industrial converters with a power of up to 500V, and high-voltage ones - up to 6000V.
• The degree of IP protection also varies. According to the type of control, emergency situations are divided into vector and scalar. All leading manufacturers of pumping equipment also offer consumers inverter units. Typically, manufacturers link converter models to specific pump modifications and provide recommendations for their use.

The buyer doesn’t even need to think much about the choice: the sales consultant will indicate to you the converter model suitable for this pump and explain to you what the features of its use are.

Pumps used in systems autonomous water supply and heating, are productive, but at the same time quite expensive equipment in terms of operation due to high level energy consumption. You can reduce costs and significantly extend the life of the pump by equipping it with a frequency converter, which we will discuss in this article.

You will learn why a frequency converter is needed and what functions it performs. The operating principle of such devices, their varieties, specifications and recommendations on the selection of converters for well and circulation pumps are given.

1 Why do you need a frequency converter?

Almost all modern pumps sold in the budget and mid-price categories are designed using the throttling principle. The electric motor of such units always operates at maximum power, and the change in fluid flow/pressure is carried out by adjusting shut-off valves, which changes the cross-section of the throughput hole.

This principle of operation has a number of significant disadvantages; it provokes the appearance of water hammer, since immediately after switching on the pump begins to pump water through the pipes at maximum power. Another problem is high energy consumption and rapid wear of system components - both the pump and the shut-off valves with the pipeline. And there can be no talk of fine-tuning such a water supply system for a house from a well.

The above-described disadvantages are not typical for pumps equipped with a frequency converter. This element allows you to effectively control the pressure created in the water supply or heating pipeline by changing the amount of electricity supplied to the motor.

As can be seen in the diagram, pumping equipment is always calculated according to the maximum power parameter, however, in maximum load mode, the pump operates only during periods of peak water consumption, which is extremely rare. In all other cases, the increased power of the equipment is unnecessary. A frequency converter, as statistics show, allows you to save up to 30-40% of electricity when operating circulation and well pumps.

1.1 Design and algorithm of operation

A frequency converter for water supply pumps is an electrical device that converts constant pressure power supply to alternating current at a predetermined amplitude and frequency. Almost all modern converters are made using a double current change circuit. This design consists of 3 main parts:

• uncontrolled rectifier;
• pulse inverter;
• control system.

The key element of the design is the pulse inverter, which in turn consists of 5-8 transistor switches. The corresponding element of the stator winding of the electric motor is connected to each of the keys. Foreign converters use IGBT class transistors, while Russian converters use their domestic analogues.

The control system is represented by a microprocessor, which simultaneously performs the functions of protection (turns off the pump in the event of strong current fluctuations in the electrical network) and control. In borehole water pumps, the control element of the converter is connected to a pressure switch, which allows the pumping station to operate in a fully automatic mode.

The operating algorithm of the frequency converter is quite simple. When the pressure switch detects that the pressure level in the hydraulic tank has dropped below the permissible minimum, a signal is transmitted to the converter and it starts the pump motor. The engine accelerates smoothly, which reduces the hydraulic loads affecting the system. Modern converters allow the user to independently set the acceleration time of the electric motor within 5-30 seconds.

During acceleration, the signal sensor continuously transmits data on the pressure level in the pipeline to the converter. After it reaches the required value, the control unit stops acceleration and maintains the specified engine speed. If the water point connected to the pumping station begins to use more water, the converter will increase the supply pressure by increasing the pump efficiency, and vice versa.

1.2 Operation of the pump in conjunction with a frequency converter (video)

If the pump you are using does not have a built-in frequency converter, then you can purchase and install such a power regulator yourself. As a rule, pump manufacturers indicate in the technical data sheet which specific converter is suitable for a given equipment model.

1. Power - the voltage converter is always selected based on the power of the electric drive to which it is connected.
2. Input voltage - indicates the current strength at which the converter remains operational. Here you need to choose keeping in mind the fluctuations that may occur in your electrical network (low voltage causes the device to stop; if it is too high, it may simply fail). Also consider the type of pump motor - three, two or single phase.
3. Adjustment frequency range - for well pumps the optimal range will be 200-600 Hz (depending on the initial power of the pump), for circulation pumps 200-350 Hz.
4. The number of control moves and outputs - the more there are, the more commands and, as a result, the operating modes of the converter you can configure. Automation allows you to set the speed of revolutions at start-up, several modes of maximum speed, acceleration rates, etc.
5. Control method - for a well pumping station, remote control, which can be located inside the house, will be most convenient, while for circulation pumps, a converter with a remote control is perfect.

If you have sifted out all the devices on the market and are faced with the fact that there is simply no equipment suitable in terms of characteristics, you need to narrow the selection criteria to the key factor - the current consumed by the motor, by which the rated power of the converter is selected.

Also, when choosing a frequency control unit, especially from domestic or Chinese manufacturers, consider the warranty period. By its duration one can indirectly judge the reliability of the equipment.

A few words about the manufacturers. The leading company in this area is Grundfoss (Denmark), which supplies the market with over 15 different models of converters. Thus, for pumps with a three-phase electric motor, the Micro Drive FC101 model is suitable, for single-phase pumps (operating from a standard 220V power supply) - FC51.

Equipment from Rockwell Automation (Germany) is more affordable in terms of price. The company offers a line of PowerFlex 4 and 40 converters for low-power circulation pumps and a PowerFlex 400 series for well pumping stations(3 parallel connected pumps can operate from one converter at once.

Keep in mind that the price of a good converter can sometimes reach the cost of a pump, so connecting and configuring such a device should be carried out exclusively by specialists.