How to adjust the pressure switch on the pumping room. Water pressure switch (installation, characteristics, design, setting)

A pressure switch is a key element in automating the operation of a pump or pumping station; it gives a signal to turn the pump on and off. Depending on the manufacturer and model, the factory settings may differ, but, as a rule, the lower threshold for switching on the pump is set to a pressure of 1.4–1.8 bar, and the threshold for switching off is 2.5–3 bar. But sometimes such threshold settings are insufficient for normal work plumbing fixtures, therefore it is necessary to adjust the water pressure switch for the pump , to pick up individual parameters enabling and disabling it.

Design and principle of operation

Before you start configuring the relay, you need to understand the design and principle of its operation. The design of the relay is quite simple and consists of contacts spring-loaded by a plate on which water pressure acts.

1. Frame.
2. Contact group for connecting the pump.
3. Terminals for connecting to the power supply.
4. Grounding terminals.
5. Nut for connecting the relay to the water supply.
6. Differential pressure adjustment spring.
7. Spring for adjusting the minimum pressure.
8. The assembly where the piston and diaphragm are located.

On a metal base, a metal platform is fixed at one end, which can be raised and lowered under the action of a piston. The piston is driven by water pressure. There are two springs (6,7) installed on the platform, a large spring (7) counteracts the force of the piston (water), thereby balancing it. The small spring (7) does not come into action immediately, but after the platform rises to a certain height, and as soon as the platform touches the smaller spring, the forces of both springs begin to oppose the piston and the resistance to the piston force increases, from this moment the platform needs to rise quite a bit. so that the contacts open and the pump stops. A small hinge with a spring is responsible for opening and closing the contacts. As soon as the platform rises above this hinge, the contacts bounce down and the electrical circuit is opened, as soon as the action of the force of the piston (water) weakens, the platform drops down and the contacts close.

A large spring is responsible for turning on the pump, that is, for the lower pressure limit, and with the help of a small spring, the moment of turning off the pump is adjusted, or rather, the difference between turning on and off is set.

Customization

Based on the operating principle of the relay, its setting consists in changing the stiffness between the platform, which is acted upon by the water pressure and the contacts. The adjustment is carried out by changing the stiffness of the spring, which is either compressed or loosened by adjusting nuts. Before starting the adjustment, you need to fix the pressure gauge indicators while turning the pump on and off. Next, disconnect the relay from the network, and remove the housing cover. Using a wrench, unscrewing or tightening the nuts, set the required parameters:

• if it is only necessary to change the lower switching threshold (increase or decrease), then you need to press or release the nut on the spring (7);
• to increase or decrease the upper limit of the pump shutdown, you need to screw or unscrew the nut on the spring (6), when tightening, we raise the pump shutdown limit, and when unscrewing, on the contrary, we lower it, increasing the difference between on and off;
• if you need to change two parameters at once, then first the lower limit is adjusted using the spring (7), and then we set the difference using the spring (6);

All changes must be monitored with a pressure gauge. It is worth considering that by changing the pressure difference, we reduce or increase the duration of the pump operation, and this will be reflected in the change in pressure in the water supply network. If the pressure difference is small, then the pressure in the network will be "even" without visible differences, but the number of pump starts will increase, which may affect its service life.

When making adjustments, it must be remembered that the upper pressure should not be higher than the maximum pressure that the pump can create (you can see it in the pump's passport characteristics). The upper pressure should not exceed more than 80% of the maximum allowable pressure for a particular model, and these parameters are indicated in the instructions for the relay. Also, before adjusting, you need to check the air pressure in the tank pear - it should be less than the lower threshold for switching on the pump by 0.2 bar. Another regulation requirement is the switch-on and switch-off pressure difference, it must be in the range of 1-1.5 bar. When changing the parameters, it is impossible to tighten the nuts all the way, this can lead to the fact that the relay will stop working altogether.

Video

This video shows how to adjust the pressure switch for a pump:

The pressure switch is a part of the pumping station that is responsible for starting and stopping the pumping equipment when a certain pressure in the hydraulic tank is reached. As a rule, when buying a pumping station, the factory settings are set on the pressure sensors. As a result, the unit, adjusted by the manufacturer, reacts to certain indicators for starting and stopping the pump. Usually, the factory settings for switching on are set in the range of 1.5-1.8 atm., And the settings for switching off the device are triggered when the pressure hits the range from 2.5 to 3 atm.

But sometimes, for more efficient operation of the station in certain conditions, it is necessary to change the device settings. In this case, the pressure switch of the pumping station is adjusted. From our article you will learn how to do it yourself, and the video at the end of the article will help you more clearly understand the process.

So that you can properly adjust this relay with your own hands, you should understand the features of its design and understand the principle of operation of the unit.

The pressure switch of the pumping station is a metal base, on the top of which is fixed contact Group, two spring adjusters of different sizes and terminal block... In the lower part of the steel plate, a membrane cover is attached, under which there is a steel piston and the membrane itself, as well as a quick-release nut for fixing to an adapter installed on pumping equipment. All these parts are covered with a plastic lid. This, in turn, is attached to the screw part of the large regulator. This cover can be easily removed if necessary with a wrench or screwdriver.

As a rule, relays in pumping stations of water supply can differ in configuration, shape and location. individual elements, but usually they have the same design as we described above. Sometimes the relay can be completed additional elements, allowing to protect the unit from running "on dry" and to protect the motor from overheating, for this the device will measure the temperature of the pumped liquid.

The principle of operation of this device is as follows:

1. Under the action of the pressure of the water coming from the pumping equipment, the membrane, due to the increase in air pressure in the second chamber, presses on the piston, which actuates the contact group.
2. This group is mounted on a steel platform equipped with two hinges. Depending on what position it takes, the contacts through which the voltage of 220 V flows to the pump unit can close or open, thereby causing the pump to start or stop.
3. To balance the piston pressure, a regulator spring is used to act on the platform to install the contact block. The compression force of the spring is adjusted by means of the corresponding nut.
4. As the amount of water in the system decreases due to the consumption by the consumer, the air pressure in the water supply tank drops. As a result, the spring, overcoming the action of the piston, closes the contact group, which leads to the start of the pump.
5. As there is more water in the tank, the air pressure increases. This causes the piston to gradually move the contact platform in spite of the force of the spring. However, the opening of the contacts does not occur immediately, but after the platform has been displaced by a certain distance. This value depends on how much the second small spring will be compressed. It, like the large spring, is located on the stem with a nut. As soon as the contacts open, the pump unit stops working.

From this it turns out that in order to adjust the switching pressure of the water supply unit, it is necessary to correctly adjust the compression force of the large spring. The pressure regulated by this element is also called the lower one. To adjust the upper pressure in the water supply system, it is necessary to adjust the actuation of the small spring. The compression force of this element allows you to set the difference between the cut-off and cut-off pressure.

Setting the pressure switch of the pumping station may be necessary if the owner's factory settings do not settle or they are lost. However, before proceeding with the adjustment, it is necessary to properly prepare the storage tank.

Hydraulic tank preparation

Hydraulic tank, storage capacity or a hydroaccumulator is a sealed reservoir in two parts. In one part, in the form of a rubber bulb, water accumulates. And the other part is the space between the walls of the pear and the inner surface of the hydraulic tank, into which a certain amount of air is pumped.

Since water accumulates in the pear, it is connected to the water supply system. Air injection into the second chamber can be performed using a conventional car pump... Thanks to this air, the pear is compressed with water, which helps to maintain a certain pressure in the water supply pipes. Due to this, after opening the tap, the movement of water through the pipeline occurs under pressure without turning on the pump.

Attention: if the air pressure in the hydraulic tank is selected incorrectly, it will not be possible to achieve the optimal operation of the system.

Too high or low value can lead to frequent starting and stopping of the pump, which negatively affects the life of the device. A lower value can lead to excessive stretching of the pear and its rapid failure.

Hydraulic tank preparation sequence:

1. Before pumping air into the hydraulic tank or before checking the indicators, it is necessary to drain the water from the pipeline. To do this, open the bottom tap. As a result, the pear in the storage tank will be empty.
2. The air injection and pressure test can now be performed. It should be 10 percent less than the bottom figure. If you have not yet configured the system and do not know what the lower value should be, then the adjustment is done as follows:

• if the volume of the hydraulic tank is 20-25 liters, then we set the pressure in the range of 1.4-1.7 bar;
• with roominess storage tank within the range of 50-100 liters, the indicator must be set in the region of 1.7-1.9 bar.

Important: do not leave the accumulator bulb without water for a long time. From this, its walls can dry out or stick together. The air pressure in the hydraulic tank must be checked every month.

Relay setting

With the correct air pressure in the accumulator and clean filters, you can start setting the water relay in the pumping unit. We carry out the adjustment work in the following sequence:

1. After turning off the pump, we drain the water from the pipeline. To do this, open the bottom tap in the system. Using a screwdriver or wrench, remove the cover from the relay.
2. We turn on the pump that will pump water into the system.
3. At the moment of turning off the pump unit, it is necessary to record the readings of the pressure gauge. This will give you the current top pressure.
4. After that, it is worth slightly opening the crane, which is located at the highest point of the system. If you have a single-level system, then open the tap farthest from the pump. When the pressure drops to a certain value, the pump unit will start up again. You should note the gauge readings at the time of start-up and write them down again. This will find the current lower pressure. Subtracting the results obtained, you will get the pressure difference for which your relay is tuned. In addition to recording readings, evaluate the head from the open tap (the farthest in the system).
5. If the head is insufficient, then the lower pressure must be increased. To do this, the unit must be disconnected from the power supply and tightened the nut on a large spring. If you need to reduce the pressure, then the spring should be weakened.
6. Let's move on to setting the pressure difference, which you have already learned by subtracting the found indicators. Optimum performance should be within 1.4 atm. If your result is less, then this can give you a more even flow of water, but more frequent starting of the pump. This can lead to premature wear of the machine. If your result exceeds optimal indicators, then the work will take place in a more gentle mode, but the difference between the extremely high and low pressure will become noticeable. To adjust this parameter, you need to turn the nut on the small spring. In order to increase the pressure difference, it is necessary to increase the compression force. Loosening the spring will reverse the action.
7. After making the adjustment, it is worth checking its effectiveness. To do this, the water is drained from the system again, the power supply is connected to the pumping equipment and the unit starts up. Further steps are repeated until the relay settings suit you.

Attention: the second (small) spring is very sensitive, so its adjustment should be done very carefully, turning the nut a small turn.

Initial setup

If the springs on your relay are completely slack, you will have to re-adjust from scratch. In this case, the work is carried out in the following sequence:

1. They start the pumping equipment and pressurize the system to a level when the water pressure from the faucet farthest from the pump does not become more or less acceptable for you. Let us assume that measuring device showed at this moment a value of 1.5 bar. We turn off the pump.
2. Now you need to disable pumping station from the power supply, open the cover on the relay and start tightening the nut on the large spring until you hear a characteristic click, indicating that the contacts are closed.
3. The relay cover is installed in place and the pumping equipment is started. In this case, the pressure must be brought to 2.9 bar.
4. Now the unit needs to be disconnected from the power supply again, open the cover on the relay again and tighten the nut of the small spring until you hear a click of the opening of the contacts.
5. After the settings have been made, the relay will operate at a lower value of 1.5 bar and turn off the pump at an upper pressure of 2.9 bar. We return the cover on the relay to its place, and connect the station to the mains.

Video instructions for adjusting the pressure switch of the water supply unit with your own hands:

One of the reasons that leads to submersible pumping unit failure is the lack of water in the system when the pump is wasted. After all, water for such pumps is a natural coolant, and also acts as a lubricating fluid. It is to prevent this situation that a water pressure switch is installed.

When water stops entering the system, the relay contacts open and the pump turns off, and only after a sufficient water level appears, the relay turns on the pump.

Setting the water pressure switch for the pump is necessary to maintain the pressure in the system.

And what is it for normal level pressure?

Having a screwdriver and wrench you can adjust the pressure switch yourself. The pressure switch is important element circuits in the pumping equipment connection diagram.

The pressure in the tank is checked. Manufacturers, as a rule, set the relay at the following levels: in the on state - 1.5 atm., In the off state - 2.5 atm.

The entire system must be disconnected from electrical network, and there should be no water in the tank. The pressure in the tank is checked with a pressure gauge for cars. These pressure gauges are the most accurate.

When adjusting the water pressure switch, the following steps must be taken:

The adjustment can be carried out a large number of times until you find the necessary parameters for yourself.

Water pressure switch rating for pump

When choosing a pressure switch for water, you must rely on the following indicators:

• the installation of the relay should not be complicated in order to make it on your own;
• setup and adjustment is simple;
• based on customer reviews, you need to choose a quality device;
• the pressure switch must be waterproofed;
• the relay must have a powerful motor;
• the service life must be at a high level.

Also, when choosing a relay, its type is determined: electronic or mechanical it will be.

Today the following models are the most popular on the market:

Water pressure switch for pump malfunction

The pressure switch, due to its constant operation, is subject to rapid wear despite the small number of parts. And depending on which relay, automatic or mechanical, the following malfunctions differ.

Idling protection

The pressure switch protects the pump from idle move and will allow pumping equipment to start operating only after a certain amount of water appears in the well.

Idle operation can be established based on the following indicators:

• by pressure, reflected on the manometer;
• by the amount of water supplied through the water supply system.

The water pressure switch does not turn off the pump

If the pumping equipment does not turn off, then, most likely, the pressure switch has not been correctly adjusted. Those. the maximum and minimum pressure levels are incorrectly set.

The lower pressure level is set with a nut on a large spring, and the upper pressure level is set with a nut on a smaller spring. All indicators need to be adjusted.

Also, one of the reasons for not turning off the pump is the accumulated mechanical particles in the relay.

To eliminate it, it is necessary to remove the relay cover, inspect internal state and o clean the elements, if necessary.

Monitoring the pressure in the system avoids plant malfunctions and breakdowns. So correct setting and the adjustment of the relay should be given maximum attention.

Factory settings

The relay is produced with preset pressure values:

Lower indicator is 1.5 bar. As soon as the pressure in the system drops to this level, the contacts are closed and the downhole or submersible pump is turned on.

Top indicator according to standard settings it is 2.5-3 bar. The maximum value is 5 bar - it is indicated on the scale of the sensor. When the set value is reached, the contacts are broken - the pump is turned off.

The difference between the high and low values ​​is called the drop. It can be adjusted.

Water pressure is provided through air injection. A certain amount of air is pumped into the tank, which has a rubber container (pear) with a car nipple. The air presses on the water, which fills the pear, thereby providing correct work station.

Control measurement

Pressure control must be carried out before installing the station, and then periodically repeat measurements using a conventional automobile pressure gauge enclosed in a metal case.

For this, a plastic plug is removed on the tank. Under it is access to the nipple. The task of the owners is to maintain a pressure of 1.5 atmospheres here.... But, in principle, even 1 atmosphere is enough for a comfortable water supply for a small house. Obviously, the pressure in the tank should not drop below one atmosphere, as this will affect the operation of the entire pumping station.

If the pressure does not correspond to the established standards, the air must be vented or pumped up.

Relay adjustment

The relay is a compact unit with a plastic housing. If you remove the cover, you will find two adjusting springs with nuts under it:

• the large nut adjusts the lower pressure readings;
• and the small nut is responsible for the range between the upper and lower indicators - it is responsible for turning off the pump.

After pumping air into the tank using a car pump, it is necessary to connect the station to the power supply and observe the pressure gauge built into the system. The passport of each pump contains the necessary Technical information, which should be guided by when checking.

The limiting pressure is considered to be the one at which the pressure stops growing. If the pump continues to run. It should be disabled manually! Domestic pumps are not very powerful, so they cannot pump the tank to the limit values. And for normal operation of the unit, a range of only 1-2 atmospheres is required.

To check the lower values, turn on the tap. The relay will operate at a lower pressure reading. At this stage, the station should be turned off and adjustment started.

It includes the following steps:

1. The small nut increases or decreases the lower value (to turn on the station). To increase pressure, turn the nut clockwise. You only need to make one turn! Then turn on the power supply and check the work on the pressure gauge (to detect the moment of turning on - the lower limit). To decrease the pressure, respectively, the nut rotates counterclockwise.
2. The large nut sets the range (to turn off the station). To increase the range, tighten the nut, and to decrease it, unscrew it counterclockwise. The lower indicator does not change in this case! The moment when the pump is turned off must also be checked on the pressure gauge.

With a wide range, the station will turn on a little less often, which saves pump resources. If the range is less, the station sounds more often.

Important: the switch-on pressure (lower value) should be 0.1-0.3 atmospheres higher than the indicator in an empty tank. For example, if the air pressure when measured with a car pressure gauge through the pear nipple is 1.5 atm., The relay should be set to 1.6-1.8 atm.

What do you need to work?

To adjust, you need an 8 to 10 wrench or a screwdriver. The cover is removed with a screwdriver, and the unit is fine-tuned with a key.

The exploded view of the assembly looks like this:

Housing (1), cover (2), fastening screw (3), ON regulator (4), OFF regulator (5), terminals (6), grounding (7).

Important points

Do not fully tighten one or both nuts (all the way) - this may cause the unit to malfunction.

It is not recommended to increase the pressure by more than 80% of the pressure recommended according to the technical data sheet supplied with the relay. For example, for maximum value at 5 bar, you can set the upper value to 4 atmospheres (5 times 0.8 equals 4).

If the pump can only set the pressure to 3 atmospheres, it makes no sense to set the relay to greater importance... On average, one atmosphere is consumed per 10 meters of water column. The corresponding value will be indicated in the pump passport. For example, that it is designed for 30 meters.

It is important to take into account that the pressure is set at the same level as the station. If plumbing device is higher (on the second floor, for example), the value for shutdown will be lower (0.1 atmosphere is lost for every meter of height).

When making the adjustment, it must be remembered that the plumbing equipment, rubber hose and other elements of the system have their own pressure limits that cannot be exceeded, even if the capabilities of the relay itself and the pump allow it.

The water pressure switch is designed to control the pumping unit and maintain the pressure in the water supply network of the house at a given level. The pressure switch is very important and must be properly installed and adjusted. The entire water supply system, the safety of its functioning and the performance of other units in the system depend on the quality of the pressure switch.

The principle of operation of the pressure switch (pump control sensor)

The relay registers the water pressure in the system with a movable spring group. When the specified minimum pressure is reached, the contact closes, turning on the pumping unit. When the maximum set pressure is reached, the contact opens and the pumping unit turns off. The pressure switches are equipped with adjusting mechanisms that allow you to adjust the pressure values, and they can additionally be equipped with a "dry" forced start button, soft start equipment for the pump, additional connectors instead of terminal groups for connecting the pump, operation indication, etc.

Place for pressure switch installation

It is recommended to install a pressure switch directly at the outlet to the accumulator, where in to a greater extent pressure surges and flow turbulence during pump start-up and operation are leveled. Also, for individual models, manufacturers limit the operating conditions for the microclimate, namely, the temperature is not lower than +4 degrees. and humidity not higher than 70%. Such relays should be installed in a heated room.

Before the pump control sensor (pressure switch) in the water supply system, the following must be installed:

• Coarse water filter
• Pump and piping
• Inlet valve
• Fine water filter
• Check valve
• Draining to the sewerage system

The installation option for a pressure switch in the water supply system of a house is shown in the figure.

Modern pump models are equipped with special fittings for connecting a pressure switch, as well as built-in filters and check valve... Therefore, separate pressure switches can also be mounted directly in the pump unit. If the relay is made according to a waterproof scheme, then it can be installed with a pump and in a caisson (pit) and even directly in a well. It all depends on the chosen model and the manufacturer's recommendations for temperature and humidity.

Determination of work parameters

Before choosing a pressure switch, a pumping unit and a hydraulic accumulator must already be selected, and the operating parameters of the network must be determined:
- the maximum pressure in the system at which the pump will be turned off;
- the minimum pressure at which the pump will turn on;
- pressure in the air chamber of the accumulator.

Please note that the minimum operating pressure in the water supply system should be 0.2 atm more than the pressure in the air chamber of the accumulator. Otherwise, increased wear of the elastic membrane is possible.

Please note that the relay can be:
- power, - including power contacts to the pumping unit;
- control, - issuing a signal to the power control unit.

Check for what permissible switching power the relay is designed. And how this value relates to the selected pumping unit.

Design features and pressure setting

A pressure switch of a simple design is a small device that is equipped with a nipple for connecting to water pipe and a terminal block for connection electrical cables... The registration of pressure parameters is carried out using springs, the force of which is adjusted by threaded regulators.

The more the springs are compressed by the regulator, the more force they create, and the higher the pressure is required to operate the relay (large spring), or the greater the pressure difference must be (small spring). Those. by clamping the springs we increase the values.

Typically, pressure switches designed for household use have a factory spring setting that is fully suitable for living conditions applications and common models of pumps and accumulators. For example, the minimum pressure is 1.5 atm. The maximum pressure is 3.0 atm.

However, due to some factors (considerations), sometimes it becomes necessary to adjust the pressure.

Adjusting the pressure switch for the pump

• Relays are usually equipped with two springs with different diameters.
• A large diameter spring controls pressure levels.
• Small diameter spring - determines the level difference.
• By clamping a large spring, we increase the minimum and maximum pressure at the same time.
• By clamping a small spring, we increase the superiority of the maximum pressure over the minimum.

The video shows the process of adjusting the pressure on the relay (somewhat confused explanations about the purpose of the springs should not be misleading, and the psychological stability of the observer should contribute to understanding the difference between the readings of the pressure gauge and the voiced results)

Water pressure switch connection

The video presented shows the popular models of pressure switches, their characteristics and connection nuances are announced. Happy viewing.