Our Products

Home > Our Products > Solenoid Valves

Solenoid Valves

Characteristics : Solenoid Valves

electrovanne

Valve types

Direct action solenoid valves 2/2 and 3/2 NC or NO
The electricity supplied to the coil, generates a magnetic force that attracts the armature, which contains the seat that acts upon a passage orifice. The armature, rising, lets the fluid pass. The range of operating pressures depends directly on the attraction force of the coil.

Differential pressure solenoid valves 2/2 NC or NO
This solenoid valve uses the force of the fluid to operate the valve via a suitable integral pilot valve. The inlet pressure must always be at least the same as the minimum differential pressure figure shownon the data sheets. Using the same cois as direct acting valves much higher fluid volumes and pressures can be controlled with this solenoid valve.

Pilot operated solenoid valves with assisted lift 2/2 NC
These solenoid valves are a combinaison of the pilot operated valves and the direct acting valves. The armature is mechanically connected to the diaphragm on which there is a pilot orifice. With minimal pressures the solenoid valve acts like a direct acting valve. Total opening as well as full flow do not occur at low pressures. With higher pressures it works as a pilot operated valve with full opening.
Valve Selection

A solenoid valve should be chosen whenever the following conditions are met:

- Media with few dirt particles
- Moderate flow volumes
- Average differential pressures
- High speed in operation

Function Types

2/2 function indicates valves with inlet and outlet connections, whilst valves with 3/2 functions have 3 connections and 2 flow passages. One orifice always remains open and one closed. Connections and flow directions are shown in the symbols on each technical data sheet (DIN-ISO 1219)
 
At rest valves can be either normally closed (NC) or normally open (NO) :

- Normally closed (NC) : the valve opens when the coil is energized.
- Normally open (NO) : the valve closes when the coil is energized

Optional features

Manual Override (M)

Normally closed direct acting and pilot operated solenoid valves can be supplied with a manual override which allows the valve to be opened independently of electrical current.

Technical Information

The following points should be considered to ensure a correct choice of valve :

Connections and Nominal Diameters

Threaded connections are either "G" - inches (ISO 228) or metric. Nominal diameters (DN) are expressed in millimeters and correspond to the diameter of the valve's main orifice.

Operating pressure

Pressure values shown in this catalogue are maximum pressures expressed in bar with zero pressure at outlet. For 3/2 way solenoid valves the pressure range can vary when used in other functions or systems. The maximum working pressure (PN) that the valve can bear is generally equal to 1.5 times the maximum value of the operating pressure differential.

Flow

The flow is the quantity of fluid that passes through the valve's main orifice which has the nominal diameter (DN) shown in the tables. The flow is givenwith a constant Kv value (according to VDI/VDE 2173) that shows how many litres of water, at a temperature of 20°C, flow through the valve in one minute with a pressure difference of one bar across the valve.To determine the flow at higher pressure, multiply the Kv value by the square root of the differential pressure. Flow values shown in the selection tables are subject to a tolerance of + or - 15%.

Coil power supply

It is important that the exact voltage and frequency of the coil is used for the valve to operate correctly. Provided the coil is fitted correctly on the operator and that the armature is not obstructed, the valve can be operated for an indefinite time within the temperature limitations indicated. All solenoid valves have a shading ring to reduce vibrations caused by alternating currents.
Seal materials

Consideration of the media should be made when selecting seal and body types.

- NBR should be used for air, water, neutral gases, diesel and in general it is resistant to oils and grease from -10°C to +80°C.

- EPDM for hot waterand steam. It is resistant to bases and acids in weak concentrations from -10°C to +140°C.EPDM seals should not be used for media containing oil.
- FKM combines most of the characteristics of NBR and EPDM and is particularly suitable for hot water and hydro-carbons from -10°C to +150°C.

- PTFE is practically resistant to all media. It is rigid and is used from -20°C to +160°C.

- Ruby is a stiff material particularly suitable for heavy duty applications.

All the data shown in the selection tables refer to media with a viscosity not higher than 21 cST (3°E) (1 centistoke=1 mm2/sec).

Media and Ambiant Temperatures

Temperature limits for the media are shown and should be used as a guide to valve selection. Usually, the maximum ambiant temperature can reach +50°C for solenoid valves with coils in class "F", +70°C for class "H". For applications outside these limits please contact our technical office (+33 4 86 30 70 80).

General purpose solenoid valves

Solenoid valves shown in this catalogue, either normally open or normally closed, are intended to control the flow of fluids and cannot be used as safety valves.

Valve Installation

To ensure trouble-free operation please observe the following

Safety :

Always connect the coil's earth terminal to ground to ensure the safety of the user and installation.

Installation

Keep the valve operator in a vertical position, facing upwards. This prevents limescale or dirt particles in the operator tube which could restrict the armature or create excessive noise whilst operating.

Connections

To ensure that the solenoid valve works properly, do not connect to pipework with an internal diameter less than the nominal diameter (DN) of the valve. Clean all pipework before connection to the solenoid valve.

Flow Direction

Respect the direction of flow across the valve, shown with an arrow or by numbers on the valve body, depending on the model type.

Filtration

If the fluid contains dirt particles it is necessary to install a filter upstream of the solenoid valve. Dirt is the most frequent cause of malfunction.

Environment

Coils fitted suitable connectors have an IP65 protection class. However, it is advisable not to use the solenoid valve outside or in very damp conditions without adequate protection. Provide sufficient ventilation for the solenoid valve. During continuous service the coil of the solenoid valve becomes hot and should not be touched.