Water pressure switch for the pump: wiring diagram, device and feedback

The pressure switch is equipment that is used to maintain the specified pressure values on the pump equipment and in the line to which it is connected. What is a pressure switch for a pump, how to choose, install it? The answers to these questions you can learn from this article.

The design provides for the presence of sensors and controllers, acting as sensitive elements. They measure the readings of the monitored parameter, after which they are converted into a convenient form for processing and transmitted to the relay. Relay on the basis of this information fulfills the programmed operations and restores the regular operation of the system.

Appointment

The water pressure switch for the pump (connection diagram shown below) is used to automate the procedure for storing the set parameters. What makes this device in demand in all systems in which control is provided for processes associated with regulation in closed systems of indicators.

Classification

To date, the pressure switch is classified according to the following parameters:

• Limit levels of measurement and control.
• Availability of additional contacts.
• Method of installation.
• Degree of protection.
• Type and level of the input signal.
• Type of power supply (external or standalone).

Design Features

The water pressure switch for the pump (the connection diagram is given below) is an electronic mechanical equipment that turns off and starts the pump set at certain pressures in the water supply network.

The devices manufactured by different manufacturers are structurally similar, the differences are only in minor details. Disconnection and power supply of the pump unit are carried out by opening and closing the contact group - the main element of the relay. Also, the equipment includes two springs and a piston with a membrane.

After being connected to a special station adapter, the fluid pressure begins to affect the membrane, which in turn affects the piston that is connected to the contact group.

The contact group on the opposite side is acted upon by a large spring, the compression of which is regulated by means of a corresponding nut. If, due to the water intake in the water supply system, the pressure drops, the spring overcomes the effect on the piston side, and the contact group closes, supplying power to the pump.

When the pressure in the pipeline increases, the piston will gradually move the platform with the contacts, overcoming the counteraction of the spring. However, the contacts do not immediately open, this only occurs as a result of moving to a certain distance, depending on the compression ratio of the small spring. Like a large spring, it is planted on a rod with a nut. As a result of opening the contacts, the pump set is switched off.

The principle of operation of the station

The water supply system automatically supplies water to the tap under a certain pressure. The structure of the station includes: a hydro accumulator, a pump, and a water pressure switch for the pump. The connection scheme involves pumping a fluid that moves through a pipeline and passes into a hydraulic accumulator, which is a kind of reservoir for accumulating liquid.

Inside the accumulator there is a membrane, which when the liquid enters compresses the air and increases in size. After that, when the crane is opened, water starts flowing from it with a certain pressure, when it closes, the movement of water stops.

At this point, the pressure becomes less than the set value, and the relay automatically activates the pump and water starts to flow into the tank again. It arrives at the moment the fill limiter is activated and the pump stops using a relay.

Water pressure switch for the pump: connection diagram, operating principle

The relay is a block with springs, which are responsible for the size of the maximum and minimum values of the fluid pressure. The springs are adjusted using special nuts.

The force of water pressure is directed to the membrane, and when it falls to the minimum value, the spring is weakened. When the maximum pressure is reached, the diaphragm overcomes the resistance of the spring. This behavior of the membrane causes either water on or off. That is, as a result of the action of the membrane on the spring, the contacts located under the housing cover are closed or opened.

As soon as the liquid level indicator reaches the minimum value, the electric circuit closes, supplies voltage to the pump, which starts to work.

The pump equipment pumps the water to the maximum level, after which the electrical circuit closes, the supply of voltage is completed and the unit stops operating.

Connectivity

Consider how to connect the pressure switch (wiring diagram see below). These water connection blocks are provided with a non-standard input. The relay of household type, as a rule, has a four-inch input, professional devices can be supplied with an input of a larger size. For this reason, it is first of all desirable to take care of the adapter.

Until a certain time, when manufacturing pumping equipment, a standard part was used, called the herringbone in the people. This adapter is a brass piece of a pipeline 100-120 mm in size and 25 mm in diameter. One end is connected to the pump inlet. The outputs at the adapter are the bends for connecting the water main, pressure switch and other equipment.

At present, everything looks a little more complicated. In modern pump units, the relay is screwed directly into the equipment, or into places that at first glance are the least suitable for this.

First of all, the pump is connected to the water source, then - to the power supply. Adjustment and adjustment is the final, the third stage of the work.

Need for adjustment

Adjustment of the pressure switch for the pump (how to configure it, discussed below) may be required for the following reasons:

• If for any reason do not arrange the factory settings.
• If the assembly of the pumping station is carried out at the place of its installation.

Adjustment by own hands

If for any reason you do not have the factory settings of the pumping station, then the connection and adjustment of the water pressure switch is done by yourself. This requires a screwdriver or a wrench. You will also need a key for twisting (twisting) the control nuts. Do not forget that when the component parts of the station fail, the product loses its warranty. If the result of the violation was the incorrect connection scheme of the submersible pump, the connection as a whole was not performed correctly - all this is not a valid reason for the manufacturer.

It is necessary to start the setting by switching off the voltage relay. After that, the cover closing the relay is removed, and adjustment is made as desired, for example, to increase pressure, measure or lower the operating range.

Decrease or increase of pressure

Proceeding from the above, to reduce or increase the pressure without changing the range at which the relay trips, it is only necessary to tighten or unscrew the nut on the large regulator.

Range Range Changes

If you are satisfied, for example, with a lower threshold, and you only need to increase or decrease the upper threshold, then a smaller regulator is used.

While tightening the nut of this regulator to the right, the upper threshold will increase, without changing the lower one. If the process is weakened, the process will occur to the exact opposite, that is, the difference between them will increase or decrease.

After adjustment, the voltage is switched on, the moment when pump shutdown (upper pressure) occurred on the manometer.

It happens that the value of the switching point and the operating range are not suitable, then in this case, the adjustment must be performed by a large regulator, and then by a smaller one, by monitoring the process using a manometer.

Pressure switch for water pump: connection, price, reviews

According to customer feedback, today the relay of the Danfoss company Danfoss is more popular, its pressure range is 0.2-8 bar. The cost of such equipment is about 3000 rubles. The device from the German manufacturer Grundfos with similar characteristics costs 4,500 rubles. Italian equipment Italtecnica with standard settings will cost about 500 rubles.

Domestic devices of the firm "Gileks" are almost identical to Italian ones, however their cost is about 300 rubles. Thus, domestic production is much less expensive, and in terms of its characteristics it is almost inferior to Western models.

Experts recommend installing equipment of one manufacturer, that is, if you purchased a German pump, then the pressure switch must be from the same manufacturer.

Now you know what the connection scheme of the pressure switch looks like, how to connect it correctly, will not cause you any more questions.