Water flow relay - purpose, operating principle and independent connection. How to protect the pump from dry running Circulation pump with flow sensor

The water supply system of a private house is impossible without a pump. But you need to somehow turn it on and off, and make sure that it does not work in the absence of water. The water pressure switch is responsible for turning the pump on and off, and the presence of water should be monitored by protection against dry running of the pump. How to implement this protection in different situation and let's look further.

What is dry running of a pump?

No matter where the pump pumps water from, at times a situation arises that the water has run out - if the flow rate of a well or borehole is small, you can simply pump out all the water. If water is pumped from a centralized water supply, its supply may simply be stopped. The operation of the pump in the absence of water is called dry running. The term “idling” is sometimes used, although this is not entirely correct.

In order for the water supply at home to work normally, you need not only a pump, but also a dry water protection system and automatic on-off switching.

What's wrong with dry running, other than wasting electricity? If the pump operates in the absence of water, it will overheat and burn out - the pumped water is used to cool it. No water - no cooling. The engine will overheat and burn out. Therefore, protection against dry running of the pump is one of the components of the automation that will have to be purchased in addition. There are, however, models with built-in protection, but they are expensive. It is cheaper to buy additional automation.

How can you protect the pump from dry running?

There are a few different devices, which will turn off the pump if there is no water:

• dry running protection relay;
• water flow control devices;
• water level sensors (float switch and level control relay).

All these devices are designed for one thing - turn off the pump when there is no water. They just work differently and have different areas of application. Next, we will look at the features of their work and when they are most effective.

Dry running protection relay

A simple electromechanical device monitors the presence of pressure in the system. As soon as the pressure drops below the threshold, the power supply circuit is broken and the pump stops working.

The relay consists of a membrane that responds to pressure and a contact group that is normally open. When the pressure decreases, the membrane presses on the contacts, they close, turning off the power.

This is what protection against dry running of the pump looks like

When is it effective?

The pressure to which the device responds is from 0.1 atm to 0.6 atm (depending on factory settings). This situation is possible when there is little or no water, the filter is clogged, or the self-priming part is too high. In any case, this is a dry running condition and the pump must be turned off, which is what happens.

A protection relay is installed idle move on the surface, although there are models in a sealed case. It works normally in an irrigation scheme or any system without a hydraulic accumulator. Works more efficiently with surface pumps, When check valve installed after the pump.

When it does not guarantee shutdown in the absence of water

You can install it in a system with HA, but you will not get 100% protection against dry running of the pump. It's all about the particular structure and operation of such a system. Place a protective relay in front of the water pressure switch and the hydraulic accumulator. In this case, there is usually a check valve between the pump and the protection, that is, the membrane is under pressure created by the hydraulic accumulator. This usual scheme. But with this method of switching on, it is possible that a working pump in the absence of water will not turn off and will burn out.

For example, a dry running situation has been created: the pump is turned on, there is no water in the well/borehole/tank, and there is some water in the accumulator. Since the lower pressure threshold is usually set to about 1.4-1.6 atm, the protective relay membrane will not work. After all, there is pressure in the system. In this position, the membrane is pressed out, the pump will run dry.

It will stop either when it burns out or when most of the water supply is used up from the hydraulic accumulator. Only then will the pressure drop to critical and the relay will be able to operate. If such a situation arose during the active use of water, nothing terrible will happen in principle - several tens of liters will dry up quickly and everything will be normal. But if this happened at night, they flushed the water in the tank, washed their hands and went to bed. The pump turned on, but there was no signal to turn off. By the morning, when water collection begins, it will be inoperative. That is why in systems with hydraulic accumulators or pumping stations it is better to use other devices to protect against dry running of the water pump.

Water flow control devices

In any situation that causes the pump to run dry, there is insufficient or no water flow. There are devices that monitor this situation - relays and water flow controllers. Flow relays or sensors - electromechanical devices, controllers are electronic.

Flow relays (sensors)

There are two types of flow sensors - petal and turbine. Petal has a flexible plate that is located in the pipeline. In the absence of water flow, the plate deviates from its normal state, contacts are activated, turning off the power to the pump.

Turbine flow sensors are somewhat more complicated. The basis of the device is a small turbine with an electromagnet in the rotor. When there is a flow of water or gas, the turbine rotates, creating an electromagnetic field, which is converted into electromagnetic pulses read by the sensor. This sensor, depending on the number of pulses, turns on/off the power to the pump.

Flow controllers

Basically, these are devices that combine two functions: dry-running protection and a water pressure switch. Some models, in addition to these functions, may have a built-in pressure gauge and check valve. These devices are also called electronic pressure switches. These devices cannot be called cheap, but they provide high-quality protection, serving several parameters at once, ensuring the required pressure in the system, turning off the equipment when there is insufficient water flow.

In the case of using an automation unit, the hydraulic accumulator is an extra device. The system works perfectly when flow appears - opening the tap, triggering household appliances and so on. But this is if the headroom is small. If the gap is large, both a HA and a pressure switch are needed. The fact is that the pump shutdown limit in the automation unit is not adjustable. The pump will turn off only when it has created maximum pressure. If it is taken with a large margin of pressure, it can create overpressure(optimal - no more than 3-4 atm, anything higher leads to premature wear of the system). Therefore, after the automation unit there is a hydraulic accumulator. This scheme makes it possible to regulate the pressure at which the pump turns off.

Water level sensors

These sensors are installed in a well, borehole, or container. It is advisable to use them with submersible pumps, although they are compatible with surface pumps. There are two types of sensors - float and electronic.

Float

There are two types of water level sensors - for filling the container (protection against overflow) and for emptying - just protection against dry running. The second option is ours, the first is needed when filling out. There are also models that can work either way, but the principle of operation depends on the connection diagram (included in the instructions).

The principle of operation when used to protect against dry running is simple: as long as there is water, the float sensor is raised up, the pump can operate, as soon as the water level has dropped so much that the sensor has dropped, the contactor opens the pump power circuit, it cannot turn on until until the water level rises. To protect the pump from idling, the float cable is connected to the open phase wire.

Level control relay

These devices can be used not only to control the minimum water level and dry running in a well, well or storage tank. They can also control overflow (overflow), which is often necessary when there is a storage tank in the system, from which water is then pumped into the house, or when organizing a water supply for a swimming pool.

Electrodes are lowered into the water. Their number depends on the parameters they monitor. If you only need to monitor the presence of a sufficient amount of water, two sensors are enough. One - goes down to the level of the minimum possible level, the second - basic - is located slightly lower. The work uses the electrical conductivity of water: while both sensors are immersed in water, small currents flow between them. This means that there is enough water in the well/well/container. If there is no current, this means that the water has dropped below the minimum level sensor. This command opens the pump's power supply circuit and stops working.

These are the main ways in which protection against dry running of a pump is organized in the water supply systems of a private home. Is there some more frequency converters, but they are expensive, so it is advisable to use them in large systems with powerful pumps. There they quickly pay for themselves due to energy savings.

Flow sensor- a device that generates an output signal in the presence of a flow of liquid or gas. They are installed in pipelines and air ducts where the presence of working fluid flow is a critical parameter.

This sensor is also called flow switch, because its principle of operation is similar, with the only difference that its operation is caused not by the appearance of a control voltage on the coil, but by the presence of a flow of liquid or gas. But the result of triggering the flow sensor, as well as a conventional relay, is a change in the state of the output contacts to the opposite.

As a rule, the sensor has a normally closed (NC) and a normally open contact (NO). When a flow of working medium appears, the NC contact opens and the NO contact closes.

There are several types of flow sensors:

Petal flow switch

The figure shows a diagram of a petal-type flow sensor.

As the name implies, the main working element of this type of flow sensor is a flexible petal that is in contact with the working medium and deviates from the vertical position in the presence of flow. The petal is mechanically connected to the output contacts and changes their state when it bends itself.

Caleffi (left) and Danfoss (right) petal flow switches

Turbine type flow sensor

The figure shows a diagram of a turbine-type flow sensor.

Such sensors are a small turbine whose rotor is equipped with a magnet. When a flow of working substance passes through the device, the turbine begins to rotate, resulting in a magnetic field that is converted into electrical pulses that enter the electronic circuit of the sensor. The electronics cause the output contacts to change state when flow is present, just as in a paddle sensor.

Thus, such flow sensors have two types of outputs: output contacts (NO and NC) and pulse output. The latter is used to determine the flow speed: the higher the pulse repetition rate, the higher the flow speed.

Flow sensor (turbine) for Ariston boiler

An example of this type of sensor is a flow switch gas boiler Ariston. When flow appears (when the user opens the tap hot water), the sensor generates an output signal and switches the boiler to DHW heating.

Using Flow Sensors

Flow sensors most often perform protective, informational or control functions.

The protective function is associated with detecting the presence of flow in systems where its absence can lead to emergency situations or equipment breakdowns. For example, they protect pumps, because When operating in the absence of water flow, they overheat and fail. You can also determine the lack of air flow in ventilation systems when the filter is clogged, the damper is closed, or the fan breaks down. Using a flow switch, you can detect leaks in water supply systems, determine the lack of water in storage tank etc.

The information function of the flow relay is spoken of when the presence or absence of flow is not associated with an emergency situation, but is a significant event in the system that the user needs to know about. In such cases, the sensor is used to trigger a light or sound indication, or generate a message on the operator panel.

The flow switch performs the control function when other equipment is turned on or off based on its signal. For example, in domestic hot water systems, when the user opens the tap with hot water, the gas boiler must turn on the pump and switch to the DHW heating mode. This happens just when the flow sensor is triggered after opening the tap.

Flow switch connection diagram

The following figure shows typical diagram turning on the flow sensor for the pump.

If there is no flow, NO contact 1-2 is open, and NC contact 1-3 is closed, the power circuit is open, and the pump is stopped. When a flow of water appears through the relay, its contacts change their state, the power supply circuit of the pump is closed and it turns on.

Taking good care of the equipment that supplies water significantly extends its service life and guarantees uninterrupted operation of the system. This requires not only timely inspection and proper care, but also equipping the pumps with a full set of protection devices. Preventing the possibility of a serious breakdown is much cheaper than repairing or buying a new unit. Do you agree?

Installing a water flow switch will protect the engine both surface and deep pumping equipment. After all, most often when the motor burns out, it is easier to buy a new pump than to change it. We will tell you how this important protective device works, how to choose it and include it in an autonomous water supply.

The article provides valuable recommendations on the installation of devices to protect pumps from operating in “dry running” conditions. The technology of customization for individual requirements has been analyzed. For a better understanding of the considerable amount of information, photographs, diagrams, video reviews and manuals are attached.

In household water supply systems, the action of a pumping station without water quite often occurs and threatens an accident. This problem is called “dry running”.

As a rule, the liquid cools and lubricates the elements of the system, thereby ensuring its normal operation. Even short-term dry operation leads to deformation of individual parts, overheating and failure of the equipment motor. Negative consequences apply to both surface and deep-well pump models.

Dry running occurs for various reasons:

• incorrect choice of pump capacity;
• unsuccessful installation;
• violation of the integrity of the water pipe;
• low fluid pressure and lack of control over its level, for which they use;
• accumulated debris in the pumping pipe.

An automatic sensor is necessary in order to completely protect the device from the threats posed by a lack of water. It measures, controls and maintains constant water flow parameters.

Pumping equipment equipped with a sensor has many advantages. It lasts longer, breaks down less often, and uses energy more economically. There are also relay models for boilers

The main purpose of the relay is to independently turn off the pumping station when the liquid flow is insufficient and turn it on after normalization of the indicators.

Design and operating principle

The sensor has a unique device, thanks to which it performs its direct functions. The most common modification is the paddle relay.

IN classic scheme The structure includes the following important elements:

• an inlet pipe that passes water through the device;
• valve (petal) located on the wall of the inner chamber;
• an isolated reed switch that opens and closes the power supply circuit;
• springs of a certain diameter with varying degrees compression.

While the chamber is filled with liquid, the force of the flow begins to act on the valve, moving it around its axis.

Magnet built-in with reverse side petal, comes close to the reed switch. As a result, the contacts close, turning on the pump.

The flow of water is understood as the speed of its physical movement, sufficient to turn on the relay. Reducing the speed to zero, resulting in a complete stop, returns the switch to its original position. When setting the response threshold, this parameter is set taking into account the conditions of use of the device

When the flow of fluid stops and the pressure in the system drops below normal, the compression of the spring weakens, returning the valve to its original position. Moving away, the magnetic element ceases to operate, the contacts open and the pumping station stops.

Some modifications are equipped with a return magnet instead of springs. Judging by user reviews, they are less susceptible to minor pressure surges in the system.

Leaf relays are characterized by a large number of pros. Among them are a simple and unpretentious design, instant response, no delays between repeated responses, and the use of a precise trigger to start the equipment.

Depending on the constructive solution There are several other types of relays. These include rotary devices equipped with a paddle wheel rotating in a water flow. The speed of rotation of the blade in them is controlled by touch sensors. If there is liquid in the pipe, the mechanism deflects, closing the contacts.

There is also a thermal relay that operates according to thermodynamic principles. The device compares the temperature set on the sensors with the temperature of the working medium in the system.

If there is flow, a thermal change is detected, after which the electrical contacts are connected to the pump. If there is no water movement, the microswitch disconnects the contacts. The models are characterized by high sensitivity, but they are quite expensive.

Device selection criteria

When choosing equipment that controls the force of water flow, you should carefully study it specifications.

Particular attention should be paid to the range operating temperature and the pressures for which it is designed, the diameter of the threads and mounting holes, the protection class, the nuances of application. It is also important to clarify what materials the product is made from.

Experts consider devices made of brass, stainless steel, and aluminum to be the most reliable and durable. These materials protect the structure from the critical consequences of frequent water supply systems phenomena – hydraulic shocks

When considering different modifications of the relay, it makes sense to purchase a version made of metal. The housing and working components of such devices are highly durable.

This fact allows the equipment to withstand serious loads for a long time that arise due to the significant impact of the liquid passing through the sensor.

The pressure value at which the relay operates must correspond to the power installed pump. The parameters of the water flow circulating through the pipeline depend on this characteristic.

It is advisable to choose a device with two springs that controls the operation of the pumping station according to certain lower and upper pressure marks.

The operating temperature range of the sensor directly indicates its possible area of ​​application. For example, for hot water circuits and heating systems Models with high limit temperatures are intended. For pipelines with cold water A range of up to 60 degrees is quite sufficient

Another important criterion that deserves special mention is the climatic conditions necessary for the operation of the product. This refers to the recommended air temperature and humidity level that the device needs to provide in order for it to perform at its best.

Maximum permissible loads for a specific device determines the protection class specified in the technical specifications.

When purchasing a flow sensor, you should check the thread diameter and the dimensions of the mounting holes in the equipment: they must fit perfectly with the pipeline elements. The correctness and accuracy of further installation, as well as the efficiency of the relay after installation, depend on this.

Trusted Instruments

Among the entire range of relays most in demand There are two models that are in approximately the same price category - about $30. Let's take a closer look at their characteristics.

Genyo Lowara Genyo 8A

Development of a Polish company engaged in the production of electronic equipment for control systems. Designed for use in domestic water supply systems.

Genyo allows you to provide automatic control pump: starts and stops based on actual water consumption, preventing any pressure fluctuations during operation. Also, the electric pump is protected from running “dry”

The main purpose is to control the pump and control the pressure in the pipes during operation. This sensor starts the pump when the water flow exceeds 1.6 liters per minute. It consumes 2.4 kW of electricity. Operating temperature range – from 5 to 60 degrees.

Grundfos UPA 120

Manufactured in factories in Romania and China. Maintains stable water supply in premises equipped with individual water supply systems. Prevents pumping units from idling.

Relay trademark Grundfos equipped high class protection, allowing it to withstand almost any load. Its electricity consumption is about 2.2 kW

The device’s automation starts at a liquid flow rate of 1.5 liters in one minute. The limit parameter of the temperature range covered is 60 degrees. The unit is manufactured in compact linear dimensions, significantly simplifying the installation process.

Liquid flow relays are installed for devices that require constant control and compliance with a certain operating mode. Often they are equipped with equipment at the production stage. However, there are also circumstances when a separate installation of the sensor is required.

Rules for installing relays in the system

Installing a safety device that detects the presence or absence of water flow in the system is a reasonable step in cases where it is not possible to be constantly present during the operation of the pumping equipment.

It is not required only in two cases:

1. Water is pumped from a large well with unlimited resources by a low-power pump.
2. It is possible to independently turn off the installation when the water level drops below the designated norm.

The device is installed on horizontal sections of the pipeline. In this case, you need to ensure that the membrane assumes a stable vertical position.

The device is mounted to the drain pipeline using a threaded coupling. Usually a special socket is provided for this.

If the pumping equipment does not have a hole for mounting the sensor, you can replace it with a brass tee. In addition to the relay, a pressure gauge is connected to it, showing the current pressure in the network

Before you start directly screwing the device, it is advisable to seal the threads well with flax or thread, sold in specialized departments.

It is better to wind it clockwise towards the end. This method of fastening increases the reliability of fixation.

In order not to damage the relay, you should screw it very carefully, slightly tightening it wrench. Optimal distance between the product and the pipeline - at least 55 mm

When installing a factory sensor, you need to focus on the arrow shown on the body. The direction indicated on it must coincide with the direction of flow of the liquid passing through the device.

If contaminated water is transported through the pipeline, it is recommended to install cleaning filters, placing them near the sensor. Such a move will ensure the correct operation of the product.

At the final stage installation work The dry running relay is connected to the electrical network:

• a wire core is screwed to the free ends of the two groups of contacts;
• a ground connection is attached to the sensor screw;
• the device is connected to the pump by connecting two devices with a regular wire in compliance.

After connecting to the network, all that remains is to check the functionality of the system. The fact that the device is ready for full operation will be indicated by an increase in pressure marks on the pressure gauge and automatic shutdown pump when the limit value is exceeded.

Self-adjustment procedure

For adjustment, the sensor has special bolts. By loosening or tightening them, you can reduce or increase the compression force of the spring.

This sets the pressure level at which the device will operate.

Almost always, manufacturing companies produce equipment with adjusted settings. Despite this, sometimes additional self-adjustment is required

In most cases, setting up automatic equipment is not difficult.

It is advisable to adhere to the following algorithm:

• drain the liquid from the system until the pressure mark reaches zero;
• turn on pumping unit and slowly turn the water back on;
• record the flow pressure indicator when the pump is turned off with a sensor;
• start draining again and remember the indicators at which the pumping equipment will start working;
• open the relay and use the adjusting bolt to set the minimum level of compression of the larger spring required to activate the device and start the pump (more compression increases the degree of pressure, less - reduces it);
• adjust the compression force of the smaller one in a similar way spring mechanism by setting boundaries maximum pressure, upon reaching which the relay measuring the water flow will turn off the pump.

Having completed all the described manipulations, you should make sure that the adjustments made are correct. To do this, the pipeline is filled with liquid and then drained, assessing the sensor’s response when the set values ​​are reached.

If the test result is unsatisfactory, the procedure is repeated.

Having insufficient experience and qualifications, it is better to seek help in adjustment from specialists. They will analyze the specific situation, take into account the technical characteristics of the equipment and select the most correct pressure level values

To ensure that the pipeline through which the liquid passes works properly and stably, regular annual checks of the flow sensors are carried out. If necessary, the operating parameters are adjusted.

Conclusions and useful video on the topic

Structure, components and operating principles:

The process of connecting a device in stages:

Learn more about how to adjust the trigger level in a relay:

A relay that controls the flow of water in the pipeline will significantly increase the ease of use of pumps and will extend their service life for a long time. Neglect installation safety device is extremely undesirable, since it not only automates the operation of the equipment, but also protects it to the maximum from possible problems that occur due to idling.

Do you want to install the flow switch yourself, but are a little confused about the instructions? Please ask your questions, and we and our website visitors will try to help you.

Or maybe you have successfully completed the installation and configuration of the device and want to give useful recommendations other newbies? Write your comments in the block below, add photos of the installation or setup process - your experience will be useful to many home craftsmen.

general description

The Grundfos UPA water pressure booster pump is a sealless pump with " wet rotor". For pumps with a “wet” rotor, the motor is completely immersed in the pumped water, which lubricates the parts and at the same time cools the engine.
The UPA pump's electric motor is cooled by the pumped liquid and, thanks to well-absorbed vibration, the pump operates silently.
The electric motor of this pump is separated from the stator by a protective sleeve made of stainless steel. Unique system ceramic bearings give the UPA pump unsurpassed durability and reliability.
The pumps are available in two versions:

• with a cast iron body with an internal anti-corrosion coating (UPA 15-90);
• with stainless steel housing (UPA 15-90 N).

Example UP A 15 - 90 N 160

Type range - UP
Automatic start/stop via flow switch - A
Nominal diameter of suction and discharge pipes (DN), [mm] - 15
Maximum pressure [dm] -90
Body version - Cast iron N - stainless steel

Key Features and Functions

• Operating range Delivery up to 1.5 m3/h
• Head up to 8 m
• Supply voltage 1 x 230 V
• Temperature of the pumped liquid from 2°C to + 60°C
• Temperature environment from 2°C to + 40°C
• Max. operating pressure 6 bar
• Connection G 3/4"
• Protection class: IP 42.
• Insulation class: H.
• The pump is equipped with a cable.
• The electric motor is equipped with short circuit current protection.
• The pump noise level does not exceed 43 dB, which corresponds to EEC

UPA circulation pumps are designed to increase pressure in the existing water supply system of private houses, apartments, etc. First of all, they are used to create pressure in front of water heaters ( geysers And instantaneous water heaters), washing and dishwashers. Compact UPA pumps can also be used to increase water pressure in showers or other water points.
UPA water pressure booster pump are used in open systems, and can also be connected directly to the water supply network.
UPA 15-90 (N) are equipped with a flow sensor to automatically turn on/off the pump when the tap is opened at the water collection point. To provide additional protection The electronic unit is equipped with a built-in temperature sensor. When overheating, the engine turns off; when the temperature decreases, the motor automatically turns on.
Using a switch on the terminal box, the pump is set to the desired operating mode. The small dimensions and weight of the pump allow it to be mounted directly on pipelines.

Add. Information

Grundfos UPA pumps are designed to require no additional effort. maintenance, and will not cause difficulties in care.
The high-quality performance of pumps in the UPA model line is confirmed by certificates and has a quality guarantee.

Effective operation of pumping equipment is the key to uninterrupted water supply and functioning of the heating system in a private home. If you want to enjoy the benefits of civilization every day, you must make every effort to set it up correctly.

The solution to this problem includes a wide range of work, the main one being the installation of additional equipment that will help to clearly monitor possible failures in the system and prevent pump failure.

The most popular and useful in everyday life are such auxiliary devices as: a temperature sensor, as well as a water flow sensor. It is the properties and operational features of the latter device that will be discussed in this article.

1 Purpose and benefits

In everyday life, an emergency switching on of a pump without water periodically occurs, which is considered extremely dangerous, because it can cause equipment failure. Popularly called “dry running” leads to overheating of the engine and deformation of parts.

Such negative changes occur because the water in the system performs a lubricating and cooling function. Operating in “dry running” mode, even for a short time, has a negative effect on the equipment, be it circulation or. To avoid such problems, the pumping station is equipped with automation - a water flow sensor. It will prevent negative changes in the system and avoid the cost of repairing the pump.

The water flow sensor is a device for controlling a pumping station in. In addition, this automatic device serves to increase pressure and protect the pump, which is used in heating systems.

The principle of operation of the sensor is that it monitors the power of the liquid flow and independently turns it on or off pumping station when a stream of water appears and passes through it. In this way, it is possible to prevent possible “dry running”, because the submersible or circulation pump drives the system and raises the pressure inside it only when required.

Installing a water flow sensor entails a number of positive points in operation of the pumping station:

• saving energy costs;
• reducing the risk of equipment breakdown;
• increasing pump life.

1.1 Design and operating principle

As has already become clear, the built-in water flow sensor is used in heating and water supply circulation systems of private houses. His job is to ensure that in the absence of liquid flow, machine gunners stop the pumping station and prevent “dry running”, and when water appears, they activate the equipment. The sensor obtained similar operating properties due to its design.

The device consists of a valve (“petal”), which is located in the flow part, and a reed switch. When water pressure arises, the reed valve begins to move, compressing the spring. At the same time, the magnet on the “petal” and the reed relay interact.

As a result, the contacts close, which activates the submersible or circulation pump. When there is no water and corresponding pressure in the system, the valve spring expands, moving the magnet to its original position - this causes the contacts to open and the equipment to stop.

Water flow sensor for circulation or submersible pump easy to install in an existing system, you just need to choose the right device, paying due attention to the key parameters.

1.2 Main characteristics

The purchase of a water flow sensor should be approached carefully. We recommend focusing on the following characteristics of the device:

• material of the body and working components;
• operating pressure;
• coolant temperature range;
• operating conditions and protection class;
• thread diameter.

To understand the impact each of these factors has on the operational features of the device, let’s consider them step by step. The material of the housing and operating components affect the reliability and durability of the sensor that is installed on the pump. It is desirable that the device be based on metals: stainless steel, aluminum or brass.

These materials are able to protect working elements from a powerful flow of water and hydraulic shock. Be sure to study the operating pressure level at which the sensor is capable of operating. For each circulation pump this value will be individual, so you need to calculate the appropriate parameter in advance.

There are devices that provide two levels of pump control: at the lower pressure limit of the system to turn it on and at the upper pressure limit in case of interruption or an unacceptably low level of water flow to turn off the pumping station.

A sensor with the possibility of such programming is considered optimal. When choosing equipment for controlling water flow, one cannot neglect such a parameter as the coolant temperature range.

Conditions for using devices may vary significantly. It’s one thing if you have to install a sensor in a heating system, where temperatures can reach 110°C, and quite another thing when the pump is used to turn on and supply cold water.

In the latter case, you can choose a device designed for a temperature range of 60-80°C. To ensure that the pump and purchased sensor remain operational for as long as possible, pay attention to the conditions under which the equipment should operate.

The instructions for the device must indicate the ambient temperature level and protection class. The last criterion determines the loads that the sensor installed in the pump can withstand.

To produce the correct and precision installation you will have to pay attention not only to permissible temperatures operation of the device, but also on the diameter of the connecting thread. Only with correct and high-quality joining of the elements can the effective functioning of the sensor be achieved after its preliminary installation and switching on.

1.3 About the device and characteristics (video)

2 Adjustment and connection of the sensor

The flow sensor, which is used to monitor the water level and pressure in the system, should be adjusted immediately after purchase. The process works as follows: the device is shipped with the contacts open and the calibration screw tightened.

After turning on the pump and reaching the optimal water level, the lamella moves in the direction of the liquid flow, which leads to the closure of the contacts. If the lamella does not start to move, this means that this level of water flow is not enough. If the device does not respond, you need to set a different value and perform the operation again.

There are a number of rules that will facilitate the installation of a flow sensor, the main one is that the device must be installed on a horizontal pipeline, regardless of the temperature of the water moving inside. In this case, you need to ensure that the lamella is positioned vertically.

The distance between the pipe and the device should be carefully measured - the minimum acceptable value is 55 mm. Using a threaded coupling, the sensor is connected to the drain pipeline, regardless of the water level inside.

The device must be oriented so that the arrows on its body correspond to the direction of water flow in the system. When high level coolant contamination is mounted in front of the sensor.