How to regulate the pressure at the station. How to adjust the pressure in the accumulator. When to Adjust the Relay

Setting up from scratch

Sometimes you have to deal with a relay whose springs are completely weakened. In this case, do it like this:

1. Turning on the pump, the pressure in the network is pumped up to the level at which water from the most remote or highly located tap flows with an acceptable pressure. Suppose the pressure gauge showed 1.5 atm. After that, the pump must be turned off.
2. After disconnecting the station from the mains and removing the cover from the relay, tighten the large spring until the relay clicks, closing the contacts.
3. Having closed the relay, the pump is turned on and the pressure is adjusted to 2.9 atm (1.5 + 1.4).
4. Turning off the pump again and opening the relay, tighten the small spring until the contacts open.
5. Now the relay is set to Pon = 1.5 atm and Poff = 2.9 atm. It is necessary to close it with a lid and turn on the station in the mains.

Setting the pressure switch

Common Mistakes

Relay adjustment does not always go smoothly. Here are the most common situations:

Small spring overstretched

As a result, the cut-off pressure has exceeded the maximum head of the pump.

In this case, the pump simply will not turn off.

What needs to be done:

• apply power to the pump and start it;
• as soon as the pressure on the pressure gauge stops increasing, the station must be turned off;
• opening any of the taps, drain a small amount of water;
• making sure that the equipment is completely disconnected from the mains, remove the cover from the relay and loosen the small spring until the contacts open with a characteristic click;

Now you can put the cover back on and turn on the pump.

Pressure Poff is more than 80% of the maximum allowable for this relay model

The relay of most pumping stations is designed for a pressure of 5 - 5.5 atm. This parameter is given in the product passport or on the packaging.

Consequently, the pressure Poff for such a device should not exceed 4–4.4 atm.

If this is not enough for a comfortable water supply, you will have to install a relay with a large limiting pressure.

The Pon pressure is set so high (large spring overstretched) that the pump cannot overcome it and "get" to the operating range

In this case, the station will not turn off again.

What needs to be done: before starting the adjustment, study the pump passport and find the maximum value of the pressure it develops. Usually it is indicated in meters of water column (m.w.st.). To convert it to atmospheres, the value given must be divided by 10.34. Under all conditions, Pon and Poff must be less than the maximum head the pump is capable of.

Features of relays from some manufacturers

Some relay models may have additional elements, which often confuse inexperienced owners of pumping stations.

The most typical are:

1. Dry run safety lever: most often found in expensive imported models that come with a complete set.
2. An additional spring that prevents spontaneous turning of the nuts on the adjusting springs: such a device can be observed in the RDM-5 relays installed at pumping stations Russian company Gilex Jumbo.

The presence of these elements should not confuse you, perform the settings in accordance with the instructions provided.

It is also worth mentioning the features specific to Marina and Pedrollo stations (Italy). For the first, the maximum pressure for the relay is only 3.2 atm and the springs in it have to be tightened every six months. For the latter, there is a manufacturer's recommendation regarding the air pressure in the accumulator: it should be 0.2 atm less than the Pon pressure, which at standard settings is 1.4 atm.

Relays with heavily tightened springs wear out quickly. Try to select a model with sufficient pressure margin.

In the private construction sector, there is often no possibility of central communications, including water supply. - a great way to provide your household with water. Installation and installation of the pump.

You can familiarize yourself with the technology of water purification from iron in the material.

Related video

When organizing a water supply system at home, not only a pump is needed, but also automation to ensure its operation. One of the necessary devices is a water pressure switch. This small device turns on the pump when the pressure in the system drops and turns it off when the threshold is reached. The value of the on and off parameters can be adjusted. About how this device is arranged, how to connect it and how to regulate it - in the article.

Purpose and device

In order to maintain a constant pressure in the water supply system of a private house, two devices are needed - a hydraulic accumulator and a pressure switch. Both of these devices are connected to the pump through the pipeline - the pressure switch is located in the middle between the pump and the accumulator. Most often it is located in the immediate vicinity of this tank, but some models can be installed on the pump housing (even submersible). Let's understand the purpose of these devices and how the system works.

A hydraulic accumulator is a container divided by an elastic pear or membrane into two halves. In one, air is under some pressure, in the second, water is pumped. The water pressure in the accumulator and the amount of water that can be pumped there is regulated by the amount of air pumped. The more air, the higher the pressure maintained in the system. But at the same time, less water can be pumped into the tank. Usually it is possible to pump no more than half of the volume into the container. That is, it will be possible to pump no more than 40-50 liters into a hydraulic accumulator with a volume of 100 liters.

For normal operation of household appliances, a range of 1.4 atm - 2.8 atm is required. To support such a framework, a pressure switch is required. It has two operation limits - upper and lower. Upon reaching lower limit the relay starts the pump, it pumps water into the accumulator, while pressure increases in it (and in the system). When the pressure in the system reaches the upper limit, the relay turns off the pump.

In a circuit with a hydroaccumulator, for some time water is consumed from the tank. When enough flows out so that the pressure drops to the lower threshold, the pump will turn on. That's how this system works.

Pressure switch device

This device consists of two parts - electrical and hydraulic. The electrical part is a group of contacts that closes and opens on / off the pump. The hydraulic part is a membrane that exerts pressure on the metal base and springs (large and small) with which the pump on / off pressure can be changed.

The hydraulic outlet is located on the back of the relay. It can be an outlet with an external thread or with a nut like an American. The second option is more convenient during installation - in the first case, you either need to look for an adapter with a union nut right size or twist the device itself, winding it onto the thread, and this is not always possible.

The electrical inputs are also located on the back of the case, and the terminal block itself, where the wires are connected, is hidden under the cover.

Species and varieties

There are two types of water pressure switches: mechanical and electronic. Mechanical ones are much cheaper and usually prefer them, while electronic ones are mostly brought to order.

The difference in prices in different stores is more than significant. Although, as usual, when buying cheap copies, there is a risk of running into a fake.

Connecting the water pressure switch

The water pressure switch for the pump is connected immediately to two systems: to electricity and plumbing. It is installed permanently, since there is no need to move the device.

Electrical part

To connect a pressure switch, a dedicated line is not required, but desirable - there are more chances that the device will work longer. A cable with a solid copper core with a cross section of at least 2.5 square meters should go from the shield. mm. It is desirable to install a bunch of automatic + RCD or difavtomat. The parameters are selected according to the current and depend more on the characteristics of the pump, since the water pressure switch consumes very little current. The circuit must have grounding - the combination of water and electricity creates a zone of increased danger.

Scheme of connecting the water pressure switch to

Cables are brought into special inputs on the back side of the case. There is a terminal block under the cover. It has three pairs of contacts:

• grounding - the corresponding conductors coming from the shield and from the pump are connected;
• terminals line or "line" - for connecting the phase and neutral wires from the shield;
• terminals for similar wires from the pump (usually on the block located above).

The connection is standard - the conductors are stripped of insulation, inserted into the connector, tightened with a clamping bolt. Pulling on the conductor, check whether it is securely clamped. After 30-60 minutes, the bolts can be tightened, since copper - soft material and contact may be weakened.

Pipe connection

There is different ways connecting a water pressure switch to the plumbing system. The most convenient option is to install a special adapter with all the required outlets - a five-pin fitting. The same system can be assembled from other fittings, just a ready-made version is always better to use.

It is screwed onto a pipe on the back of the case, a hydraulic accumulator is connected to the other outlets, a supply hose from the pump and a line that goes into the house. You can also install a mud sump and a pressure gauge.

A pressure gauge is a necessary thing - to control the pressure in the system, to monitor the settings of the relay. Mud collector is also a necessary device, but it can be installed separately on the pipeline from the pump. There, in general, a whole is desirable

With this scheme, at a high flow rate, water is supplied directly to the system - bypassing the accumulator. It begins to fill up after all the taps in the house are closed.

Water pressure switch adjustment

Consider the process of adjusting the most popular instance - RDM-5. It is produced by different factories. Adjustment limits vary, as different sizes of water pipes require different pressures. This device leaves the factory with a basic setting. Usually it is 1.4-1.5 atm - the lower threshold and 2.8-2.9 atm - the upper threshold. If some parameter does not suit you, you can reconfigure it as required. Such a procedure is usually necessary when installing a hot tub: a standard pressure of 2.5-2.9 atm is not enough for the desired effect. In most other cases, reconfiguration is not required.

The RDM-5 water pressure switch has two springs that regulate the pump off / on threshold. These springs differ in size and purpose:

• large regulates the limits (immediately upper and lower);
• a small one changes the delta - the gap between the upper and lower borders.

The parameters are changed when tightening or loosening the nuts on the springs. If you tighten the nuts, the pressure increases, if you loosen it, it drops. There is no need to turn the nuts strongly one turn - this is a change of about 0.6-0.8 atm, and this is usually a lot.

How to determine relay thresholds

The threshold for turning on the pump (and the lower pressure threshold on the water pressure switch) are related to the pressure in the air part of the accumulator - the minimum pressure in the system should be 0.1-0.2 atm higher. For example, if the pressure in the tank is 1.4 atm, the shutdown threshold is 1.6 atm. With these parameters, the tank membrane will last longer. But in order for the pump to work under normal conditions, look at its characteristics. It also has a lower pressure threshold. So, it should not be higher than the selected value (below or equal). Based on these three parameters, you select the switching threshold.

By the way, the pressure in the accumulator must be checked before setting - there are significant deviations from the declared parameters. Under the removable cover (in different models it looks and is located in different places) the nipple is hidden. Through it, you can connect a pressure gauge (you can use a car or the one you have) and see the actual pressure. By the way, it can be adjusted through the same nipple - increase or decrease if necessary.

The upper threshold - pump shutdown - is set automatically during adjustment. The relay in the initial state is set to some kind of pressure difference (delta). This difference is usually 1.4-1.6 atm. So if you set the inclusion, for example, to 1.6 atm, the shutdown threshold will be automatically set to 3.0-3.2 atm (depending on the relay settings). If you need more high pressure(raise water to the second floor, for example, or the system has many draw-off points), you can increase the shutdown threshold. But there are limitations:

• The parameters of the relay itself. The upper limit is fixed and in household models usually does not exceed 4 atm. It just won't work anymore.
• The upper limit of the pump pressure. This parameter is also fixed and the pump must be turned off at least 0.2-0.4 atm before the declared characteristic. For example, the upper pressure threshold of the pump is 3.8 atm, the shutdown threshold on the water pressure switch should not be higher than 3.6 atm. But in order for the pump to work for a long time and without overloads, it is better to make a larger difference - overloads have a too bad effect on the life.

That's all for choosing the settings of the water pressure switch. In practice, when setting up the system, you have to adjust the selected parameters in one direction or another, because you need to choose everything so that all draw-off points work normally, including household appliances. Therefore, it is often said that the parameters are chosen by the “scientific poke” method.

Setting the water pressure switch for a pump or pumping station

To set up the system, you will need a reliable pressure gauge, the readings of which can be trusted. It is connected to the system near the pressure switch.

The adjustment process consists in twisting two springs: large and small. If you need to raise or lower the lower threshold (turn on the pump), turn the nut on the large spring. If you turn it clockwise, the pressure rises, counter-clockwise - it falls. Turn by a very small value - half a turn or so.

The sequence of actions is as follows:

• The system is started, the pressure gauge monitors at what pressure the pump turned on and turned off.
• Press or release the large spring.
• They turn on and check the parameters (at what pressure it turned on, at what pressure it turned off). Both values ​​are shifted by the same amount.
• If necessary, make adjustments (adjust the large spring again).
• After the lower threshold is set as you want to see it, proceed to adjust the pump shutdown threshold. To do this, press or lower a small spring. Do not turn the nut on it too much - half a turn is usually enough.
• Turn the system back on and look at the results. If everything suits, they stop there.

What else do you need to know about adjusting the water pressure switch? That not all models have the ability to change the delta, so look carefully when buying. There is a pressure switch for the pump in a moisture- and dust-proof housing. They can be placed in a pit, some models can be installed directly on the pump housing if it has such an outlet.

In some water pressure switches there is also an idle (dry) relay, in general this device is in a separate case, but there are also combined ones. Idling protection is necessary so that the pump does not break if suddenly there is no water in the well or well. Some pumps have built-in protection of this type, for others they buy and install relays separately.

Initially, the pressure switch for pumping stations is configured by the manufacturer for specific on and off indicators. During the operation of the equipment, it may be necessary to correct them. Therefore, any property owner will not be hindered by information on how to adjust the automation at the pumping station.

Purpose of the pressure switch

This device is responsible for the functioning of the pump - for starting and stopping it when a specific pressure is reached in the hydraulic tank of the station. The relay consists of a metal base. In its upper part there are: two regulators in the form of springs of different sizes, a contact group and a terminal box.

If you familiarize yourself with the design and principles of operation of the device, it becomes clear how to properly set up the pressure switch of the pumping station.

At the bottom of the steel plate there is a fixed cover, and under it are located: a membrane, a metal piston, a quick-release clamping nut designed to be fixed to the adapter located on the pump. If necessary, the plastic cover attached to the large regulator can be easily removed using a screwdriver or wrench.

Relays for water supply stations differ in their shape and placement of some parts, but most often, their design is similar to that previously described. Sometimes this part of the station is completed with elements that protect the equipment from “dry” operation and prevent it from overheating, since the temperature of the water medium passing through the device is measured.

The principle of operation of the pumping station pressure switch is as follows:

1. Membrane under the pressure of the fluid supplied pumping unit, due to the increase in air pressure in one of the compartments, it begins to press the piston, which starts the contact group.
2. This group is mounted on a steel platform equipped with two hinges. In accordance with the position it occupies, the contacts that conduct a voltage of 220 V through themselves to the pump are able to open and close, leading to a stop or start of the equipment.
3. To balance the pressure of the piston, the regulator spring is activated, which acts on the platform in order to install the contact group. To adjust the compression force of the spring, a specific nut is used.
4. When residents consume water, this leads to a decrease in its volume in the system, so the air pressure in the storage tank decreases, as a result of which the spring, having overcome the action of the piston, causes the contact group to close, and this in turn starts the equipment.
5. The air pressure in the tank rises as the volume of water increases. As a result this process the piston, regardless of the resistance of the spring, moves the platform with the contacts. They do not open instantly, but only after the platform is shifted by a specific distance, depending on how much another, small spring is compressed. By analogy with a large one, it is located on a stem with a nut. The equipment stops functioning immediately after the contacts are separated.

Thus, in order to correct the starting pressure of the water supply unit, it is necessary to adjust the compression force of the larger spring. The parameter that is adjusted using this part is also called the lower one.

To change the upper pressure in the water supply system, adjustment of the functioning of the smaller spring is required. Due to the compression force of this part, it is possible to set the difference between the start and shutdown pressures of the unit.

Adjustment of the pressure switch for the pumping station may be required if the factory settings go wrong or they do not suit the owner. By default, these parameters are 1.5-1.8 bar at startup and 2.5-3 bar at shutdown. Before starting the adjustment process, the storage tank should be prepared for this.

Drive preparation

The sealed tank, which must be prepared before adjusting the pressure switch at the pumping station, is also called a hydraulic accumulator, storage capacity or hydraulic tank. It consists of two compartments, in one of them, outwardly similar to a rubber pear, water accumulates.

Another chamber into which a certain volume of air is pumped is the space between the surface of the tank and the walls of the bulb. Since water accumulates in it, it is connected to a water supply structure. To pump air into the second part, you can use a car pump.

The compression of a pear filled with liquid occurs due to the presence of air, due to which a certain amount of pressure is maintained in the pipes. After switching on faucet it provides the movement of water through pipes under pressure without the help of a pump.

In the event that the air pressure in the tank was incorrectly set, ensure that the water supply structure operates in desired mode will be impossible. If you ignore the setting of the relay of the pumping station, too low or too high a value leads to frequent stops or starts of the unit, which negatively affects the duration of its operation.

The fact is that at a reduced value, without a properly performed pressure adjustment of the pumping station, the pear is subjected to strong stretching, as a result of which it quickly becomes unusable.

The storage tank, before adjusting the pressure in the water supply system, is prepared in a certain sequence. Before pumping air into it or before checking the indicators, water should be drained from the pipeline using the bottom tap. The pear in the hydraulic tank then remains empty. Now you can start pumping air and checking the pressure.

When the pressure switch of the pumping station is adjusted for the first time and there is no relevant experience, they act as follows:

• with a container size of 20 - 25 liters, the value is set in the range of 1.4-1.7 bar;
• with a tank volume in the range of 50 - 100 liters, the parameter is set at around 1.7-1.9 bar.

Experts do not recommend keeping the pear without water for a long time, because then its walls will stick together or dry out, and it will become unusable. Regularly, at least once a month, check the air pressure in the accumulator. Then, if required, proceed to the adjustment of the relay of the pumping station.

Setting the pressure switch of the pumping station

The adjustment of the unit is started provided that the pressure in the hydraulic tank is set correctly and the filters are absolutely clean.

The technique of how to set up a pumping station pressure switch involves a number of activities in a certain order:

1. Turn off the pump and drain the liquid from the pipeline by slightly opening the bottom valve in the system. Remove the plastic cover from the relay.
2. include pump unit which pumps water into the system.
3. At the moment when the device is turned off, the pressure gauge data should be recorded. In this way, before adjusting the water pressure in the pumping station, they find out the value of the current upper value.
4. Then slightly open the tap located at the highest point of the water supply structure. If it is single-level, then open the tap, the furthest from the unit. When the pressure value drops to a certain value, the pump will start working again. At the time of starting, you should also record the data on the pressure gauge showing the lower pressure. Subtracting the obtained values, the pressure difference is obtained, to which the relay is set. In addition to fixing the indicators, it is necessary to evaluate the pressure of the water flow by opening the most remote tap in the system.
5. When it is insufficient, the lower indicator should be increased. Before adjusting the pressure in the pumping station, the device is disconnected from the power supply and pressed onto the nut with a large regulator. If you want to reduce the pressure, then the spring needs to be weakened.
6. The pressure difference before starting the adjustment is already known after the recorded readings have been subtracted. Optimal values should be located within 1.4 atm. If the result is less, then a uniform supply of liquid will be ensured, but the start-up of the equipment will become more frequent - this will lead to its rapid wear. When the result is higher than the optimal values, the unit operates in a gentle mode, but the difference between the highest and lowest pressure will become significant. Before adjusting the pressure switch of the pumping station, a nut is used to adjust the parameter on the small spring. To increase the difference between pressures, the compression force is increased. In turn, weakening the spring has the opposite result.
7. After it was possible to adjust the relay of the pumping station, check its effectiveness. The liquid is drained from the system, and the power supply is connected to the pump and put into operation. The subsequent steps are repeated until the relay settings meet the needs.

Performing the initial adjustment

When the springs are completely loosened on the pressure switch for the pumping station, the setting is made from scratch:

1. The pump is put into operation and the system is pressurized to a value when the pressure in the valve farthest from it becomes acceptable. Let's say it's 1.5 bar. The unit is turned off.
2. Then the station is disconnected from the power supply, the cover is removed from the relay and the nut on the large regulator is tightened until a click is heard, indicating that the contacts have closed.
3. The cover is put in place and the pump is started up, bringing the pressure to 2.9 bar.
4. The unit is disconnected from the power supply, the cover is opened again and the nut is pressed on the small spring until a click indicates that the contacts have opened. See also: "Correct adjustment of the water pressure switch for the pump - the basic principles of setting".

When setting up the relay, you need to follow the rule explaining what pressure should be in the water pump and in the hydraulic tank. Focus on the difference between them - it will be about 10%. For example, if the pump turn-on indicator is 1.6 bar, then the air pressure in the tank should be 1.4-1.5 bar.