General Characteristics
In this series there is a clear separation between some of the valve and the medium. the solenoid controls the opening and closing movements by means of a lever or a diaphragm. In the first case the lever penetrates the valve through an elastomeric protective sheath while, in the second case, the diaphragm is inside the valve body. Both the lever and diaphragm act as a shutter. Apart from a few models, the whole DRY range is for direct action. These solenoid valves are suitable for liquid and gaseous media in applications such as: foodstuffs, chemistry, pharmacy, bio-medicine. the wet parts are made in materials either compatible with the aggressivity of the media or not contaminating. The maximum permissible viscosity is 5°E (37 cStrokes or mm²2/s).
Materials
The valve body can be either AISI 316 stainless steel or in techopolymers such as: PEI (polyeterimmide), PPOm (modified polyphenile oxide), PSU (polysulphone), PVDF (polyvinydenfluoride), PTFE (polytetrafluorethylene), PP (polypropylene). the choice is depending on the model or the application. Sealings are available in EPDM (ethylene-propylene elastomer), FPM (fluoro-carbon elastomer), VMQ (silicone elastomer), PTFE (polytetrafluorethylene).
Coils
Internally moulded steel clamp. Insulation class F (155°C); the winding is wound by class H (180°C wires. Before being encapsulated in glass fibre reinforced PBT (polybutylene-terephtalate) the winding is vacuum impregnated with polyester resin.
Standard electrical connections (2 poles plus earth) suitable for DIN 43650 plug connections or fast crimp connections 6.3x0.8 as per DIN 46340; the micro-coils, series Z0..., are suitable for fast crimp connectors 2.8x0.5 as per DIN 46350 or for micro plug connectors. Protection class IP65 EN 60529 (DIN 43650) with coil duly fitted with the plug connector. With the exception of certain versions, all the coils have obtained SEV-ASE (Swiss) approval and are suitable for continuous duty (ED 100%).
Special models on request
For special application we can supply specially designed solenoid valves having different performances and/or materials; eg valve body in POM (polyoxymethylene-polyacetal), sealing in PFPM (perfluorate elastomer), coils with domestic (IMQ) and international (VDE, UL and so on) approvals, coils with insulation class H (180°C), latching coils (pulse operation).
Voltages
The standard voltage ratings are: 12-24V in DC and 24-110-220-230V/50Hz in AC. Other voltages and frequencies are available on request. the voltage tolerances are: +10° -5% in DC; +10% -15% for AC.
Response Time
The time requested to pass from fully open to fully closed or vice-versa is a function of the size of the orifice, the operating system, the voltage value, the typ of medium, the relative pressure and temperature and the pressure drop (Dp). Depending on the diameter of the orifice, the responce time is about few tens of milliseconds depending on the models.
Useful Life
The useful life of the solenoid valve is influenced by the pressure, temperature, type of medium and the voltage. Generally speaking, these solenoid valves are reliable for more than 2 million cycles and, special surface treatments enable to overcome 8 millions cycles.