Pumping stations DIY relay repair

In detail: pumping stations do-it-yourself relay repair from a real master for the site my.housecope.com.

Sometimes the pumping station malfunctions. The water pressure in the pipeline decreases or the equipment stops functioning within the specified pressure limits. Often the reason for this situation is the failure of the pressure switch or violation of its settings.

Measurement and correction of pressure level

The pumping station is automated by means of a mechanical pressure switch. It controls the on and off of the pump, thereby maintaining a stable pressure in the water supply. If there are problems with this, it is necessary to measure the pressure level generated by the station and bring it in line with the standard settings.

Pumping equipment manufacturers usually set the following parameters:
• from 1.5 to 1.8 atm. - to turn on the pump;
• from 2.5 to 3 atm. - to turn off.

Before you start setting up the relay, you need to check the compressed air pressure in the accumulator tank. To do this, after disconnecting the station from power, open the tank lid (arrow in the figure). Then, using a conventional car pump with a built-in pressure gauge, we measure the pressure. Its level should be within 1.5 atm.

If the measured parameter is less than the specified value, it must be raised using the same car pump. It is advisable to carry out this procedure regularly. It is important that the air in the tank is under constant and equal pressure. This will ensure normal operating conditions for the accumulator and extend its service life.

After adjusting the pressure, the equipment should work normally. If the problems persist, you should start adjusting the relay settings. It should be remembered that the pump shutdown threshold cannot be set higher than the pressure level for which it is designed.

Video (click to play).

Adjustment of pressure switch settings

All configuration actions are performed when the station is in operating mode. Therefore, we connect the system to the network and wait for the pump to raise the pressure in the pipeline and turn off the engine on its own. Then you need to perform the following procedure:

1. After removing the relay cover, fully loosen the nut holding the smaller spring.

2. Set the minimum pressure level, upon reaching which the pump will turn on. This is done by rotating the nut of the larger spring.

3. Open the tap and drain the water. In this case, the moment the pump is turned on should be noted. If the value of this indicator is unsatisfactory, we repeat the adjustment procedure.

4. Set the pump off parameter. To do this, start the system and wait for the relay to activate. If its value is not satisfactory, we make the adjustment by rotating the nut of the small spring until an acceptable result is obtained.

If, after carrying out all the above actions, it was not possible to adjust the relay, most likely it is out of order. Then we are left with two options. Either replace the relay or repair it.

Imagine that you can simply turn on the tap to get water in the country. That it is not necessary to fill containers with buckets for basic hygiene procedures, cooking, cleaning. To do this, you just need to install pumping equipment with a pressure sensor, but first you need to figure out its device, do you agree?

Our article in fine detail will introduce you to a pressure switch for a pumping station. You will learn how the device works, how it activates and stops pumping.We describe in detail the popular options for pressure sensors and how to adjust them.

The author of the article lists the technological nuances and methods of setting the relay. This information is ideally complemented by useful diagrams, photo and video applications.

The device, small in size, belongs to the group of automatics serving pumping equipment. Its functionality is possible only in conjunction with a hydraulic accumulator. Despite its small size, the relay performs a number of important functions:

allows all devices to operate in a given mode;
responsive to changes in on / off thresholds;
activates and stops the pump when critical values are reached.

Simply put, it regulates the automatic process of pumping water in independent water supply circuits with a membrane tank. The adjustment is carried out during the switching of electrical circuits when two pressure parameters in the system are reached, taken as the upper and lower limits.

Buying a pumping station, you get a set of equipment, part of which is a pressure switch. Externally, models of different brands and series are similar, but may differ in shape, size, body color, setting method and location. When self-assembling automation, it is necessary to study the characteristics of the devices and select the most suitable for a specific system.

The devices are adapted for convenient installation and maintenance of the pumping station. Most often, they are fixed with a union at the inlet of the accumulator, but they can also be mounted in the cold water system pipe in the immediate vicinity of the device.

The pressure control relay has a simple collapsible design, thanks to which the user can independently adjust the operation of the accumulator, narrow or expand the parameters.

The internal parts are arranged in a durable plastic case that resembles an irregularly shaped box. It has a smooth surface and only 3 external working elements: two sleeve clamps for electrical cables coming from the mains and the pump, and a ¼, ½, 1 inch metal branch pipe for connection to the system. The thread on the branch pipe can be both external and internal.

Inside there is a base to which the working elements are attached: large and small springs with adjusting nuts, contacts for connection, a diaphragm and a plate that changes its position depending on the increase / decrease of pressure parameters in the system.

The contacts of two electrical circuits, which are closed when the limiting pressure parameters are reached, are located under the springs, which are fixed on a metal plate. When the pressure rises, the membrane of the hydraulic tank deforms, the pressure inside the pear increases, the mass of water presses on the plate. That, in turn, begins to act on the large spring.

When compressed, the spring is activated and opens the contact, which supplies voltage to the motor. As a result, the pumping station is shut down. With a decrease in pressure (usually in the range of 1.4 - 1.6 bar), the plate rises to its original position and the contacts close again - the motor starts to work and pump water.

When buying a new pumping station, it is recommended to test the equipment to make sure that all components are working properly. Checking the performance of the relay occurs in the sequence described below. An example is the Haitun PC-19.

Mechanical models do not have an indication and control panel, but they can be equipped with a forced start button. It is needed to make the device function.

There are many universal models that are sold separately from the pumping stations and can be used to assemble the system yourself. When purchasing a relay or an automation unit, it is necessary to rely on the characteristics of the device. They can be found in the technical documentation.It is important that the capabilities of the relay match those of the rest of the equipment.

It should be based on the nominal pressure, but the upper limit of the working pressure is also important. Consider the electrical data and the maximum water temperature. The required parameter is the IP class, which denotes dust and moisture protection: the higher the value, the better.

Connecting thread sizes are indicated in inches: for example, ¼ "or 1". They must match the dimensions of the connection socket. The dimensions and weight of the devices themselves are approximately the same and are secondary characteristics.

It should also be remembered that there are built-in and detail models. Most of the commercially available devices are universal: they can be connected directly to the hydraulic tank or mounted on a pipe.

Electronic relays have the same functions as mechanical ones: they are responsible for the water supply and protect the pump mechanism from dry running. They are more capricious than simple models, and are sensitive to suspended particles in water. To protect the device, a strainer filter is installed in front of its connection.

One of the differences from the traditional model is the delayed shutdown of the pump. If, when the pressure rises, the mechanical device works quickly, then the electronic analogue turns off the equipment only after 10-15 seconds. This is due to the careful attitude to technology: the less often the pump is turned on / off, the longer it will last.

Some switch models, as well as automation units, work without a hydraulic accumulator, but their functionality is limited to simpler use. Suppose they are great for watering a vegetable garden or pumping liquid from one reservoir to another, but they are not used in the water supply system at home.

At the same time, the technical characteristics of the devices are the same as those of traditional relays: the factory setting is 1.5 atm., The shutdown threshold is 3 atm., The maximum value is 10 atm.

The collapsible design of the device and the setup instructions were not invented in vain. Factory parameters rarely meet the requirements of the water supply system, as well as the volume of the accumulator.

With the help of the setting, you can not only "adjust" the upper and lower limits to the optimal values, but also make the operation of the equipment more gentle - for example, reduce the number of pump starts / stops. To do this, it is enough to slightly increase the range between working pressures - delta.

You may also encounter an incorrect setting of the factory model. If the delta was incorrectly coordinated and made too small, then the pump will constantly turn on and off, responding to a minimum increase in parameters.

By manipulating the springs, you can achieve a change in the pump shutdown threshold, as well as adjust the volume of water in the accumulator tank. It is generally accepted that the larger the delta, the greater the volume of liquid in the tank. For example, with a delta of 2 atm. the tank is 50% filled with water, with a delta of 1 atm. - by 25%.

First, let's recall the general rules of adjustment:

to increase the upper limit of operation, that is, to increase the shutdown pressure, tighten the nut on the large spring; to reduce the "ceiling" - to weaken it;
to increase the difference between the two pressure indicators, we tighten the nut on the small spring, to reduce the delta, we loosen it;
clockwise movement of the nut - increase in parameters, against - decrease;
for adjustment, it is necessary to connect a manometer, which shows the initial and changed parameters;
before starting the adjustment, it is necessary to clean the filters, fill the tank with water and make sure that all pumping equipment is working.

All adjustment actions are carried out only after testing the system and detecting low performance or obvious errors in operation.It also happens that the station stops working due to a blockage that clogs the filter or one of the narrow pipes.

Let us examine the cases when it is really necessary to refer to the adjustment of the pressure switch. This usually happens when buying a new device or when there are frequent shutdowns of the pump. Also, adjustment is required if you got a used device with knocked down parameters.

At this stage, you should check how correct the factory settings are, and, if necessary, make some changes to the operation of the pump.

In order to follow the progress of the work, it is recommended to write down all the data obtained on a piece of paper. In the future, you can return to the initial settings or change the parameters again.

In this case, we forcibly turn off the pumping equipment and act in the following order:

We turn on, and wait until the pressure reaches the maximum mark - let's say 3.7 atm.
We turn off the equipment and lower the pressure by draining the water - for example, to 3.1 atm.
Lightly tighten the nut on the small spring, increasing the value of the differential.
We check how the shutdown pressure has changed and test the system.
We set up the best option by tightening and loosening the nuts on both springs.

If the cause was a wrong initial setting, it can be solved without buying a new relay. It is recommended to regularly, once every 1-2 months, check the operation of the pressure switch and, if necessary, adjust the on / off limits.

There can be many reasons when the pump does not turn off or does not turn on - from blockage in communications to engine failure. Therefore, before you start disassembling the relay, you should make sure that the rest of the pumping station equipment is working properly.

If everything is in order with the rest of the devices, the problem is in the automation. We turn to the inspection of the pressure switch. We disconnect it from the fitting and wires, remove the cover and check two critical points: a thin connection pipe to the system and a block of contacts.

If the cleaning measures did not help, and the adjustment of the position of the springs was also in vain, most likely, the relay cannot be further used and should be replaced with a new one.

Suppose you have an old but working device in your hands. Its adjustment takes place in the same order as the setting of a new relay. Before starting work, make sure that the device is intact, disassemble it and check that all contacts and springs are in place.

Practical video tips will help you better understand how to adjust the new pressure switch of the pumping station if the parameters for some reason do not suit you. You will also learn how the dry running device is different.

Recommendations for setting up automation:

Professional advice for correct adjustment:

Comparative characteristics of two types of relays:

Pumping station device

The principle of operation of the pumping station is based on the operation of a pressure switch, which ensures the autonomy of the entire system. When turned on, the pump starts pumping water into the hydraulic tank, as it fills up to a predetermined level, the relay activates and turns off the pump.

Also, the relay is triggered when the tank is empty, when the pressure in the tank falls below the set limit. This principle of operation ensures the maintenance of a constant water level in the hydraulic tank, which makes the water supply of the house from a well or a well, in terms of convenience, comparable to the central water supply in an apartment.
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The connection of the pumping station must be carried out with the obligatory installation of a check valve (it is desirable that the valve be equipped with a mechanical filter strainer).

The valve will prevent the liquid from draining from the water intake pipe into the well when the pump is turned off, as a result of which water will be supplied to the taps immediately after the station starts operating, the filter will clean the working environment from abrasive impurities that can clog the system from the inside. The check valve is installed on the lower opening of the water intake pipe

Also keep in mind that even at the stage of connecting the pumping complex, it is necessary to take measures to prevent equipment freezing in the winter season. This can be done in two ways: by installing the unit in a caisson - an insulated plastic well up to 1 m deep, or by placing it in the basement of the house, from which a long intake pipe is drawn.

All pipes located above the level of soil freezing must be carefully insulated. When starting the station for the first time, it is necessary to fill the pump with water, for which a filling hole is provided in the upper part of its body.

One of the main factors in the malfunction of any pumping station is idling... Modern complexes have a built-in dry-running sensor that turns off the pump motor when the water mirror falls below the level of the water intake pipe.

If your equipment does not provide such a sensor, we recommend purchasing it separately and installing it - such spare parts for pumping stations are not expensive, but significantly extend the service life of the equipment.

The most common mistake made by beginners who decide to install a pumping complex for water supply is the wrong selection of equipment. For example, the pump capacity is 3 m 3 / hour, and your family consumes 5 m 3 / hour - in this case, the equipment will turn on much more often than it is permissible, which will lead to its accelerated wear. The same happens when the volume of the accumulator is incorrectly selected.
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Initially, we note that when choosing pumping equipment, it makes sense to give preference to equipment from trusted manufacturers. In this case, if repairs are needed, you can easily purchase spare parts for pumping stations or use the services of the company's service center, while it is extremely difficult to find components for cheap Chinese pumps.Consider the most frequent malfunctions pumping stations and the technology for their elimination with their own hands:

The pump is running - there is no water. Check the non-return valve, if it does not close, then the water will not be able to rise through the pipeline, but will flow down. Make sure the pump is filled with water. Wear on the impeller is also a possible cause.

The pump is running - the water comes in jerks.The problem is caused by insufficient pressure in the hydraulic tank, which is caused by damage to the diaphragm or depressurization of its body. Try to pump air into the tank, the normal pressure should be at the level of 1.5-1.6 atm, if it drops, inspect the tank for cracks, if they are absent, it is necessary to change the membrane.

The pump does not start. There can be many reasons - oxidized contacts of the pressure switch, damaged motor winding, damage to the electrical cable, wear of the starting capacitor. The most difficult case is a motor burned out due to dry running, which can only be restored by replacing the stator winding.

The pump hums but does not work. Check if the voltage in the mains is not reduced, if it is normal, then most likely the pump impeller is clogged with sand or silt, disassembly and cleaning of the pump will be required.

Dismantling the pumping stationThe reason that the pumping station does not gain pressure is a damaged membrane in the accumulator. The membrane is a rubber pear-shaped container that divides the tank space into two parts - for water and air. During operation, it wears out, which leads to cracks and loss of tightness.You should not make an attempt to restore a worn out membrane, rationally replace it with a new one, since the cost of such a part does not exceed 500 rubles. The nuances of replacement depend on the design of the accumulator in your station; as standard, the tank has a neck for draining water, which is hermetically sealed with a lid.To replace it, you need to remove the cover and unscrew the pressure ring, which is fixed to the body with bolts. By removing the ring, you can remove the membrane and install a new one in its place.
to the menu ↑The pressure switch of the pumping station is a sensor that is responsible for automatically turning on and off the pump at different levels of filling the accumulator. The setting of the pressure switch of the pumping station is carried out by the manufacturer and it is often not worth interfering with the factory calibration of the sensor, since equipment breakdowns resulting from improper adjustment are not guaranteed.However, if you need to re-tune the station to a certain operating mode, you will have to adjust the sensor. To do this, drain all the water contained in the tank and check the air pressure level, it should be 90% of the standard operating pressure for switching on. You can adjust the amount of air in the tank using a nipple located on the tank body. Image - Pumping stations do-it-yourself relay repair

Setting the pressure switch of the pumping station

On the pressure switch, you will see 2 springs - large and small, the first of them is responsible for the shutdown pressure, the second for the pump activation pressure. The springs are fixed with nuts, turning which you can change the boundary pressure levels.

To increase, the nut is tightened, to decrease, it is loosened. Keep in mind that the set pump cut-off pressure should not exceed 95% of the maximum pressure indicated in the technical passport of the station.

And the last tip - do not confuse a hydraulic accumulator and a full-fledged storage tank. The main task of the accumulator is to reduce the number of pump starts, which reduces its wear, while the storage tank serves as a container for storing the reserve amount of water.

Modern stations are equipped with hydraulic accumulators with a capacity of 25 to 75 liters, which will not be enough in the event of a prolonged power outage. Therefore, the next purchase, after purchasing a pumping station, should be a spacious storage tank.

The pumping station is automated by means of a mechanical pressure switch. It controls the on and off of the pump, thereby maintaining a stable pressure in the water supply.

The pumping station in certain situations can cause disturbances and malfunctions. As a result of this, the water pressure is minimized or the operation of the structure is disrupted in the specified range of the required pressure. The reason for the failure of the device is usually a faulty pressure switch or incorrectly set settings.

The process of automation of the station takes place thanks to the operation of the pressure switch. It is this element that controls the on and off mode of the electric pump. With its help, a stable level of pressure in the waterways is carried out. At the initial stage, it is recommended to check the pressure level indicators at which the station modes operate. All pump station manufacturers adhere to the same standard settings:

1.5 - 1.8 atm. necessary to turn on the electric pump;
2.5 - 3 atm. provide a device shutdown mode.

A common mistake is trying to control all pressure parameters at once. Experts strongly recommend checking the indicators of the effect of compressed air masses in the accumulator tank.

Before starting work, it is necessary to de-energize the pumping power station, open the plastic cover located on the front side of the tank. It is recommended to measure the pressure with a pressure gauge on the car pump. With the obtained values less than one and a half atmospheres, a subsequent increase in the pressure regime with the help of a pump for a car is necessary. In the future, it is recommended to check it regularly.

For a full-fledged process of functioning of the battery membrane and a long period of its operation, it is necessary to maintain a constant mode of uniform pressure of air masses in the tank.

After successfully raising the pressure readings, the station will start operating as usual. If this does not happen, it is recommended to start detailed adjustment of the settings and relay modes.

The extreme indicator of the threshold for turning off the pumping device should not exceed the pressure level of the specified parameters. Otherwise, it will ensure the continuous operation of the electric pump and the impossibility of creating the required pressure.

The process of adjusting the settings is universal for all models of domestic pumping power plants.

The adjustment takes place in the working condition of the equipment. At the beginning, it is necessary to connect the system to the network and expect a rise in the pressure level in the pipeline routes. With the subsequent disconnection of the electrical device, it is recommended to perform a number of manipulations:

Open the relay cover and reduce the degree of pressure of the smaller spring by loosening the nut.
Turning the nut of the larger spring, we carry out the process of adjusting the indicators of the level of the lower pressure. This will allow the pump to be turned on later.
At the next stage, experts recommend opening the tap and draining the liquid. In the process, it is necessary to detect the pressure indicator at which the pump was put into operation. If the value of the indicator turned out to be unsatisfactory, you need to repeat the adjustment and adjustment procedure.
We set the required indicators for the shutdown mode of the electric pump. To carry out this action, you need to start the system and wait for the moment the relay is triggered. If unsatisfactory results are obtained, adjustment is carried out by turning the nut of the small spring until the desired result is obtained.

If all the above manipulations did not help to establish the operation of the relay, it is out of order. In this case, professional repair or complete replacement of the element is required.

Repair of a pumping station is a typical operation, with the help of which the efficiency of the functioning of an autonomous water supply source is maintained.That is, such work, sooner or later, will be faced by any owner of a well or well.

Therefore, every homeowner whose dwelling is equipped with an autonomous water supply system must master at least the primary skills in repairing pumping stations.

In this article, we will consider the diagnosis of typical malfunctions and the subsequent repair of domestic pumping stations. Moreover, all the repair work discussed in this article can be performed by anyone with at least rudimentary plumbing skills.

The design of the pumping station consists of three units:

The pump itself (vibration or centrifugal type).
Storage capacity (tank or battery).
Control relay (float type or pressure sensor).

And all of the above nodes interact with each other in the following way:

Pumping station in operation

The pump pumps water from the well into a tank or accumulator.
The pressure sensor turns on the pump at the minimum water level in the tank or accumulator and turns it off - at the maximum level. Moreover, a mechanical float-type sensor operates in the tank, and an electronic pressure sensor functions in a hydraulic accumulator with an elastic membrane.

And, of course, breakdowns or failures in the operation of at least one unit will lead to a halt in the operation of the entire station. After all, each structural element of such a unit has an equal impact on its functionality.

Typical system breakdowns include the following problems:

Frozen water tore apart the pumping station housing

Power outages. Without it, the pump and some sensors will not work.
Water interruptions. The debit of some wells does not allow the stations to operate at full capacity for a very long time. And the water level in the source can simply decrease, dropping below the end of the intake pipe.
Failure of the pressure switch or float valve. In this case, the naos simply does not turn on.
Failure of the pump. In this case, no water flows into the tank.
Depressurization of a tank or battery. In this case, the liquid does not enter the internal water conduit, and the surrounding room will most likely be flooded.

That is, in order to maintain the station in a working condition, it is necessary, at least, to take care of the supply of electricity and the correspondence of the water level in the well to the immersion depth of the intake pipe. Well, the full service cycle involves the timely repair of each station unit.

For the full functioning of the pumping station, it is necessary to periodically inspect and repair all components and mechanisms of this unit. Moreover, a preventive examination is carried out at a specific frequency, and breakdowns happen whenever you like.

Before eliminating a breakdown, it must also be diagnosed, having determined the cause of the failure by indirect signs. And further in the text we will consider typical indirect signs of breakdowns and ways to eliminate them.

Failure of the supply pipeline

The pump rotates, water does not enter the system - this situation is familiar to many owners of autonomous wells. The reasons for this failure lie in the depressurization of the pipeline joints, failure of the check valve or ejector. In addition, such symptoms may indicate a lack of water in the source or in the working chamber of the pump.

Elimination of such a failure occurs as follows:

Check the water level in the well

First, with the help of a special expansion tank, water is poured into the pump, or rather into its working chamber. Then the station starts up again. Did not help? Then go to the next procedure.
Secondly, the water level in the well is checked. If it is below the water intake point (the end of the intake pipe), then you will have to build up the intake section of the pipeline or wait until the water rises to a static level. Isn't that the reason? Then let's move on to the next step.
Third, the integrity of the pipeline is checked.That is, it is removed from the well and examined for fractures and other defects. Damaged areas are replaced with new ones.

In addition, these problems can be triggered by power failures, when the pump simply does not have enough voltage to reach full power. Therefore, before all the above manipulations, just check the voltage at the outlet. And if there is less than 170 volts, then the problem lies with the power engineers.

Malfunction of the hydraulic tank (accumulator)

With this breakdown, the pumping station works in jerks. That is, it turns on, pumps water into the tank and turns off, after a very short period of time. Moreover, such a cycle repeats and repeats, provoking irritation of the owner of the unit.

There is only one reason for this failure - the depressurization of the accumulator. That is, the membrane in the drive has burst or the battery case itself has leaked. And diagnosing such a breakdown can be very simple: press the drive nipple - if water comes out of it, then the membrane burst, and if air comes out, then problems are somewhere in the case.

Accordingly, the membrane is replaced with a new one (sometimes together with a hydraulic accumulator), the body is sealed (in a problem area). And air is pumped into the inner cavity of the drive (through the nipple).

This is the most serious breakdown. Moreover, its consequences may look different. For example, if the pump does not turn on, then the reason for such a failure may be the lack of electricity in the network, and burned out contacts, and a burned out anchor. Therefore, first we check the light by turning on the light bulb, then we sort out the contacts in the connection box, and after that we go to the anchor.Well, if the pump turns on, but does not rotate, then, most likely, the condenser in the starting system has burned out or the impeller of the centrifugal system has stuck to the body. To eliminate this problem, you just need to "spin" the impeller. And if the unit starts working and continues to function after switching on / off, then the problem is eliminated. Otherwise, you need to "sort out" the capacitors.Pressure switch malfunctionThis problem occurs when the pump runs continuously and does not turn off. And since its operation is controlled by a pressure switch, the whole problem lies in a malfunction or failure in the regulation of this unit.The defective relay is replaced with a new one, and the unsettled one is adjusted again.Moreover, the pressure switch is adjusted as follows: Image - Pumping stations do-it-yourself relay repair

The body of the control unit is opened, revealing access to two regulating springs - a large one, with the help of which the lower pressure is set, and a small one, with the help of which the upper pressure is set.
The adjustment itself is carried out by turning the tension screw or nut. Correspondingly, turning clockwise increases the adjustable value, and counterclockwise decreases the modified parameter. And manipulation of the large spring allows you to raise or lower the minimum pressure in the system, and adjusting the small spring changes the difference between the minimum and maximum pressure.

It should be noted that all the above manipulations should be carried out only by experienced specialists, and only under the condition of complete control of the pressure at the outlet from the system using a pressure gauge that secures the safety valve.

Moreover, the lower pressure should not be less than 1.5 atmospheres, and the upper one should not be more than 5.5-6 atmospheres. Otherwise, you will lose all plumbing and household appliances connected to a poorly regulated pipeline.

Adjusting the pressure switch for the water pump - setting the on and off levels Image - Pumping stations do-it-yourself relay repair

One of the most important control elements of a water pumping station is a pressure switch. It provides automatic switching on and off of the pump, controlling the water supply to the tank according to the specified parameters... There are no clear recommendations on what the values of the limiting levels of the lower and upper pressures should be.Each consumer decides this individually within the permissible norms and instructions.

Structurally, the relay is made in the form of a compact block with springs of maximum and minimum pressure, the tension of which is regulated by nuts. The diaphragm, connected to the springs, reacts to changes in the pressure force. When the minimum value is reached, the spring is weakened, and when the maximum level is reached, it is compressed more. The impact on the springs causes the relay contacts to open (close), switching off or on the pump.

The presence of a relay in the water supply system allows ensuring constant pressure and the required water pressure in the system. The pump is automatically controlled. Correctly set levels of minimum and maximum pressure ensure its periodic shutdown, which contributes to a significant increase in trouble-free service life.The sequence of operation of the pumping station under the control of the relay is as follows:

The pump pumps water into the tank.

The water pressure is constantly increasing, which can be monitored on the pressure gauge.

When the set upper limit pressure level is reached, the relay activates and turns off the pump.

As the water pumped into the tank is consumed, the pressure decreases. When it reaches a lower level, the pump will turn on again and the cycle will repeat.

The main parameters of the relay:

Lower pressure (switch-on level). The relay contacts, which turn on the pump, close, and water enters the tank.
Upper pressure (cut-off level). The relay contacts open, the pump turns off.
The pressure range is the difference between the two previous indicators.
The value of the maximum allowable shutdown pressure.

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In the process of assembling the pumping station, special attention is paid to setting the pressure switch. The ease of operation of the water supply system, as well as the terms of trouble-free service of all components of the device, depends on how correctly its limit levels are set.

At the first stage, you need to check the pressure that was created in the tank during the manufacture of the pumping station. Typically, the factory setting is set to 1.5 atmospheres and off to 2.5 atmospheres. Check this with an empty tank and a pumping station disconnected from the mains. It is recommended to check with an automotive mechanical pressure gauge. It is housed in a metal case, so measurements are more accurate than using electronic or plastic gauges. Their readings can be affected by both the room temperature and the battery charge level. It is desirable that the scale limit of the pressure gauge be as small as possible. Because on a scale of, say, 50 atmospheres, it will be very difficult to accurately measure one atmosphere.

To check the pressure in the tank, you need to unscrew the cap that closes the spool, connect the pressure gauge and take a reading on its scale. The air pressure should be checked periodically thereafter, eg once a month. In this case, water must be completely removed from the tank by turning off the pump and opening all the taps.

Another option is also possible - to carefully monitor the pump shutdown pressure. If it increases, this will mean a decrease in air pressure in the tank. The lower the air pressure, the more water supply can be created. However, the pressure spread from a completely filled to practically empty tank is large, and all this will depend on the preferences of the consumer.

Having chosen the desired operating mode, you need to install it, bleeding off excess air for this, or pump it up additionally. It must be borne in mind that you should not reduce the pressure to a value less than one atmosphere, and also pump it over too much. Due to the small amount of air, a rubber container filled with water inside the tank will touch its walls and wipe off.And excess air will not make it possible to pump a lot of water, since a significant part of the volume of the tank will be occupied by air.

In pumping stations, which are delivered assembled, the pressure switch is pre-configured for the optimal option. But when installing it from various elements at the place of operation, the relay setting must be carried out without fail. This is due to the need to ensure an effective relationship between the relay settings and the tank volume and pump head. In addition, it may be necessary to change the initial setting of the pressure switch. The procedure should be as follows: After the air pressure in the tank is adjusted, you need to connect the pumping station to the electrical network. The pump will start pumping water. It will turn off after reaching the set maximum pressure. This is the top level. On each device, during its manufacture, the limiting pressure and the maximum allowable pump head are indicated, their excess is unacceptable. This is determined by the cessation of pressure growth. In such cases, the pump must be switched off manually. If the maximum pressure value does not coincide with the recommended level in the instructions, make the appropriate adjustment by rotating the small nut, opening the relay cover for this. Image - Pumping stations do-it-yourself relay repair

The lower pressure is measured in the same way. To do this, you need to open the tap and drain the water from the tank, observing the readings of the pressure gauge. Gradually, the pressure will drop, and when it reaches the lower limit, the pump will turn on again. This is the lower level, its value is also shown by the pressure gauge. Bring the pressure to the recommended level by turning the large nut. It should be about 10% higher than the air pressure in the tank, otherwise accelerated wear of the rubber membrane is possible.

In practice, the power of the pumps is chosen such that it does not allow pumping the tank to the extreme limit. Usually the cut-off pressure is set a couple of atmospheres above the cut-off threshold.

It is also allowed to set limit pressure levels that differ from the recommended values. In this way, you can set your own version of the operating mode of the pumping station. Moreover, when setting the pressure difference with a small nut, one must proceed from the fact that the starting point of reference should be the lower level set by the large nut. The upper level can only be set within the limits for which the system is designed. In addition, rubber hoses and other plumbing fixtures also withstand pressure no higher than the design pressure. All this must be taken into account when installing the pumping station. In addition, the excessive pressure of water from the tap is often completely unnecessary and uncomfortable.

Adjustment of the pressure switch is practiced in cases where it is necessary to set the levels of the upper and lower pressures to the specified values. For example, you want to set the upper pressure to 3 atmospheres, the lower - 1.7 atmospheres. The adjustment process is as follows:

Turn on the pump and pump water into the tank until the pressure on the pressure gauge is 3 atmospheres.
Switch off the pump.
Open the relay cover and slowly rotate the small nut until the relay picks up. Clockwise rotation of the nut means an increase in pressure, in the opposite direction - a decrease. The upper level is exposed - 3 atmospheres.
Open the tap and drain the water from the tank until the pressure on the manometer is 1.7 atmospheres.
Close the tap.
Open the relay cover and slowly rotate the large nut until the contacts engage. The lower level is exposed - 1.7 atmospheres. It should be slightly higher than the air pressure in the tank.

If high pressure is set for shutdown and low pressure for shutdown, the tank is filled with a large amount of water and there is no need to turn on the pump frequently. Inconvenience occurs only due to the large pressure drop when the tank is full or almost empty.In other cases, when the pressure range is small, and the pump often has to be pumped up, the water pressure in the system is uniform and quite comfortable.