Imagine that to get water in the country, you can simply open the tap. What does not need to fill buckets with containers 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 deal with its device, agree?
Our detailed article will introduce you to the pressure switch for the 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 material lists the technological nuances and methods of setting up the relay. The information presented is ideally complemented by useful schemes, photos and video applications.
The role of the pressure switch in the water supply system
The small-sized device belongs to the automation group serving the pumping equipment. Its functionality is only possible in conjunction with a hydraulic accumulator.
Despite its small size, the relay performs a number of important functions:
- allows all devices to function in a given mode;
- sensitively reacts to change of thresholds of inclusion / switching off;
- activates and stops the pump when critical values are reached.
Simply put, it regulates the automatic process of pumping water in independent water supply schemes with a membrane tank. Adjustment is made during the switching of electrical circuits when the system reaches two pressure parameters, adopted as the upper and lower limits.
When buying a pumping station, you get a set of equipment, of which a pressure switch is a part. Externally, models of different brands and series are similar, but may differ in shape, size, color, case, setting method and location.
With self-assembly of automation, it is necessary to study the characteristics of devices and choose the most suitable for a particular system.
The arrangement of devices involved in organizing the water supply of a private house from a well or well. The relay controls the operating pressure in the network, and the manometer displays the current parameters
The devices are adapted for convenient installation and maintenance of the pumping station. Most often, they are fixed by a fitting at the inlet of the accumulator, but can also be mounted in the pipe of the HVS system in close proximity to the device.
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Original Grundfos Pressure Switch
Relays with integrated pressure gauge AL-KO
Domestic pressure switch Whirlwind
Gardena brand equipment for summer cottages
Design and principle of operation
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 coupling clamps for power cables coming from the mains and pump, and a metal pipe ¼, ½, 1 inch for connection to the system. The thread on the nozzle is both external and internal.
To remove the device case, it is necessary to arm yourself with a flat screwdriver and slowly and carefully unscrew the plastic recessed screw located above the axis of the large spring
Inside there is a base to which the working elements are attached: large and small springs with adjusting nuts, contacts for connection, a membrane and a plate that changes its position depending on the increase / decrease of the pressure parameters in the system.
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Grounding terminals
Terminals for phase and zero
Big spring and its purpose
Small adjustment spring
The contacts of two electrical circuits, which are closed when the pressure limits are reached, are located under the springs, which are mounted on a metal plate. When the pressure rises, the membrane of the hydraulic tank is deformed, the pressure inside the pear increases, the mass of water presses on the plate. That, in turn, begins to act on a large spring.
When compressed, the spring trips and opens the contact that supplies voltage to the motor. As a result, the pumping station is turned off. 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 equipment to make sure that all components are operational. Checking the performance of the relay occurs in the sequence described below. As an example, the Haitun PC-19 model.
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Before connecting the station to the network, it is necessary to install a check valve and fill the tank with water. An electronic pressure switch with a power of 1.1 kW starts working at 1.5 atm and should turn off when it reaches 2.5 atm.
If you turn off the tap, thereby turning off the water supply, after a few seconds the pressure in the hydraulic tank rises to the maximum, the relay will work and stop the station. The upper pressure limit can be adjusted manually.
For testing, it is necessary to close / open the tap several times. The pressure will then increase, then decrease, respectively, the relay should operate every time. By the manometer, you can track the real working pressure limits - they do not always coincide with the declared
The device must turn off the operation of the station in the event that the water runs out in the source. The pressure also rises sharply and an emergency shutdown occurs. An orange lamp lights up on the display panel
Pump station with automation unit
Pressure gauge integrated in the relay housing
Equipment monitoring
Dry running alarm
Mechanical models do not have an indication and control panel, however, they can be equipped with a push button. It is necessary to make it function.
Relay selection criteria for the pump
There are many universal models that are sold separately from pumping stations and can be used to assemble the system yourself. When purchasing a relay or 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 the characteristics of the capabilities of the rest of the equipment.
Before buying an automation unit or relay, carefully study the technical data of the model. In most cases, they are standard: nominal pressure from 1.5 atm., Maximum - 3 atm.
It should be repelled from the nominal pressure, but the upper limit of the working pressure is also important. It is necessary to take into account electrical indicators and the maximum temperature of the water. An obligatory parameter is the IP class, which indicates dust and moisture protection: the higher the value, the better.
The sizes of the connecting thread are indicated in inches: for example, ¼ inch or 1 inch. They must match the size of the connection piece. 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 remote models. Most of the devices on sale 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 water supply and protect the pump mechanism from dry running. They are more moody than simple models, and are sensitive to suspended particles in water. To protect the device, a strainer strainer is installed in front of the connection point.
In fact, an electronic device is an automation unit with a convenient display and button system, which makes it possible to carry out adjustment without disassembling the device
One of the differences from the traditional model is the delay in shutting down the pump. If the mechanical device responds quickly with increasing pressure, the electronic analogue turns off the equipment only after 10-15 seconds. This is explained by a careful attitude to technology: the less often the pump turns on / off, the longer it will last.
Some arrow models, as well as automation units, work without a hydraulic accumulator, but their functionality is limited by simpler use. Suppose they are perfect for watering the garden or pumping liquid from one tank to another, but are not used in the water supply system of the house.
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 trip threshold is 3 atm., The maximum value is 10 atm.
Reasons to Customize
The collapsible design of the device and the setup instructions were invented for good reason. Factory parameters rarely meet the requirements of the water supply system, as well as the volume of the accumulator.
Before the procedure for correcting the relay, be sure to check the serviceability of the accumulator and the functioning of the water supply system to the house, otherwise you can incorrectly set the operating parameters
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 sparing - for example, reduce the number of on / off switching of the pump. To do this, it is enough to slightly increase the range between working pressures - the delta.
You may encounter incorrect configuration of the factory model. If the delta is incorrectly coordinated and made too small, the pump will constantly turn on and off, responding to a minimum increase in parameters.
Instrument Adjustment Recommendations
By manipulating the springs, you can achieve a change in the threshold for turning off the pump, 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%.
To achieve a delta of 2 atm., You must set the lower pressure value, for example, at 1.8 atm., And the upper at 3.8 atm., Changing the position of the small and large springs
First, recall the general rules of adjustment:
- to increase the upper limit of operation, that is, to increase the shut-off pressure, tighten the nut on a large spring; to reduce the "ceiling" - weaken it;
- to increase the difference between the two pressure indicators, we tighten the nut on a small spring, to reduce the delta - weaken it;
- clockwise nut movement - increase in parameters, against - decrease;
- to configure, you need to connect a pressure gauge that 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 poor performance or obvious errors in the work. It also happens that the station stops working due to a blockage that clogs the filter or one of the narrow nozzles. There is another article on our website where the process of adjusting the pressure switch is described in more detail - follow the link to familiarize yourself with the material.
Practical relay setup examples
Let us examine the cases when a reference to the adjustment of the pressure switch is really necessary. This usually happens when buying a new device or when frequent pump shutdowns occur.
You will also need to configure if you got a used device with lost parameters.
Connect a new device
At this stage, you should check how correct the factory settings are, and if necessary, make some changes to the pump.
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We turn off the energy, completely empty the system from the water until the pressure gauge reaches the zero mark. We turn on the pump and follow the readings. We remember at what value it turned off. Then we drain the water and remember the parameters at which the pump starts working again
We twist a large spring to increase the lower limit. We check: we release the water and remember the value of turning on and off. The second parameter should increase along with the first. Adjust until we reach the desired result.
We perform the same actions, but with a small spring. Care must be taken, as the slightest change in the position of the spring responds to the pump. Tightening or loosening the nut a bit, we immediately check the result of work
Having finished all manipulations with the springs, we take the final readings and compare them with the initial ones. We also look at what has changed in the operation of the station. If the tank began to fill up in a different volume, and the on / off intervals changed, the setting was successful
Stage 1 - Equipment Preparation
Stage 2 - adjustment of the amount of inclusion
Stage 3 - adjustment of the shutdown value
Stage 4 - testing the system
To monitor the progress of work, it is recommended to record all the data received on a piece of paper. In the future, you can return to the initial settings or change the settings again.
The pump has stopped turning off
In this case, forcibly turn off the pumping equipment and act in the following order:
- We turn it on, and wait until the pressure reaches its maximum mark - suppose 3.7 atm.
- We turn off the equipment and lower the pressure by draining the water - for example, to 3.1 atm.
- Slightly tighten the nut on the small spring, increasing the differential value.
- We check how the shutdown pressure has changed and test the system.
- We adjust the best option by tightening and loosening the nuts on both springs.
If the reason was in the wrong initial configuration, it can be solved without buying a new relay. It is recommended to regularly check the operation of the pressure switch once every 1-2 months and, if necessary, adjust the on / off limits.
Situations Not Requiring Adjustment
There can be many reasons when the pump does not turn off or on, from clogging in communications to engine failure. Therefore, before you start disassembling the relay, you should make sure that the rest of the equipment of the pumping station is working properly.
If everything is in order with the other devices, the problem is in the automation. We proceed 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 the contact block.
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Clogged pipe connection to the hydraulic tank
Relay Inlet Cleaning
Clogged electrical contacts
If cleaning measures did not help, and adjusting the position of the springs was also in vain, most likely the relay is not subject to further operation and should be replaced with a new one.
Suppose you got an old, but working device in your hands. Its adjustment occurs in the same order as the configuration of a new relay. Before starting work, verify the integrity of the device, disassemble it and check whether all contacts and springs are in place.
Practical video tips will help you better understand how to adjust the new pump station pressure switch if the parameters do not suit you for some reason. You will also learn how the dry running device is different.
Recommendations for setting up automation:
Professional tips for proper adjustment:
Comparative characteristic of two types of relays:
To correct the operation of the pressure switch, specialists are usually not invited, since this is a simple procedure that takes a little time. You can leave the factory settings, however, even minimal adjustment will help to prolong the operation of the pump and hydraulic tank, and also optimizes the work of the station.
Do you have personal experience in adjusting the relay for the pump and can you share practical advice with visitors to our site? Please leave your comments, ask questions, share experiences in the block below.