1. A solenoid valve is an electrically controlled valve which, depending on the control signal, remains in one of two positions:
- open position
- close position
The valves of this type use the phenomenon of an electromagnetic field induced by the current flowing through the coil, which generates a force that sets the core in motion (valve head). These valves are used to control the flow of liquid and gaseous media.
2. Each solenoid valve consists of the following functional units:
- main valve, in which the actuated valve head (poppet, membrane, piston, etc.) closes or opens the flow port, stopping or allowing the medium to flow through the valve
- electromagnet (coil) together with the moving core, which is the driving force of the valve head
3. The valve is opened or closed due to the movement of the core pulled into the center of the electromagnet after applying the control voltage to the coil. The core is placed in a sealed sleeve inside the electromagnet coil. The design ensures full internal and external tightness of the valve.
4. Coils differ in construction, control voltage (DC direct, AC alternating), its size, power consumption and IP protection (against water and dust). The principle of operation is always the same: the current flowing through the coil induces a magnetic field that generates the force raising the core.
5. A very important characteristic of solenoid valves is their unidirectional feature. The medium may only flow in the direction indicated by the arrow on the valve body.
Shall mean a moveable part of the valve which cuts-off medium flow
Shall mean a Tightness of the internal spaces of the valve that are in contact with the medium relative to the atmosphere
Shall mean a Tightness of the inlet space (for the valve in the closed position) in relation to the outflow space and other internal spaces of the valve.
Shall mean the medium pressure at the inlet port of the valve (P)
Shall mean the medium pressure at the outlet port of the valve (A)
Shall mean a pressure difference between the inlet (P) and outlet (A) ports of the valve (pressure drop on the valve)
Shall mean a minimum pressure differential at which the valve can be normally operated
Shall mean a maximum pressure differential at which the valve can be normally operated
Shall mean the maximum inlet pressure declared by the manufacturer at which the valve can be operated, assuming that the differential pressure is contained in range: ΔPmin ÷ Pmax
Shall mean the highest inlet or outlet pressure, which does not cause unsealing or damage to the valve (proof pressure is used for tightness tests of an installation). The valve cannot operate at this pressure.
Shall mean a time interval between the electrical signal and the attainment of the maximum flow rate.
Shall mean a time interval between the electrical signal and the valve head attaining the closed position
Shall mean a temperature range (minimal and maximum) of the media and air surrounding a valve, for which the manufacturer declares the possibility of valve application
Shall mean a number of cubic meters per hour of water flow through the valve (at a temperature between 5°C and 40°C) by pressure drop of 1 bar across the valve
Shall mean volumetric flow expressed in units [m3/h]
Shall mean air flow rate at a specified pressure difference declared by the manufacturer, corrected to reference conditions