Series VXD Specific Product Precautions 1 Be sure to read before handling. Refer to front matter 41 for Safety Instructions, pages 17 to 19 and the Operation Manual for 2 Port Solenoid Valves for Fluid Control Precautions. Please download it via our website, http://www.smcworld.com Selection Warning Design Design 1. Cannot be used as an emergency shutoff valve etc. The valves presented in this catalog are not designed for safety applications such as an emergency shutoff valve. If the valves are used in this type of system, other reliable safety assurance measures should also be adopted. 2. Extended periods of continuous energization The solenoid coil will generate heat when continuously energized. Avoid using in a tightly shut container. Install it in a well-ventilated area. Furthermore, do not touch it while it is being energized or right after it is energized. 3. Liquid rings In cases with a flowing liquid, provide a bypass valve in the system to prevent the liquid from entering the liquid seal circuit. 4. Actuator drive When an actuator, such as a cylinder, is to be driven using a valve, take appropriate measures to prevent potential danger caused by actuator operation. 5. Pressure (including vacuum) holding It is not usable for an application such as holding the pressure (including vacuum) inside of a pressure vessel because air leakage is entailed in a valve. 6. When the conduit type is used as equivalent to an IP65 enclosure, install a wiring conduit etc. 7. When an impact, such as water hammer etc., caused by the rapid pressure fluctuation is applied, the solenoid valve may be damaged. Give an attention to it. 2. Fluid 1) Type of fluid Select an appropriate valve with reference to the table below for the general fluid. Before using a fluid, check whether it is compatible with the materials of each model by referring to the fluids listed in this catalog. Use a fluid with a kinematic viscosity of 50 mm2/s or less. If there is something you do not know, please contact SMC. 2) Flammable oil, Gas Check the specifications for leakage in the interior and/or exterior area. 3) Corrosive gas Cannot be used since it will lead to cracks by stress corrosion or result in other incidents. 4) Depending on water quality, a brass body can cause corrosion and internal leakage may occur. If such abnormalities occur, exchange the product for a stainless steel body. 5) Use an oil-free specification when any oily particle must not enter the passage. 6) Applicable fluid on the list may not be used depending on the operating condition. Give adequate confirmation, and then determine a model, just because the compatibility list shows the general case. 3. Fluid quality 1) Use clean air. Do not use compressed air that contains chemicals, synthetic oils including organic solvents, salt or corrosive gases, etc., as it can cause damage or malfunction. 2) Install an air filter. Install an air filter close to the valve on the upstream side. A filtration degree of 5 μm or less should be selected. 3) Install an aftercooler or air dryer, etc. Compressed air that contains excessive drainage may cause malfunction of valves and other pneumatic equipment. To prevent this, install an aftercooler or air dryer, etc. 4) If excessive carbon powder is generated, eliminate it by installing a mist separator on the upstream side of valves. If excessive carbon powder is generated by the compressor, it may adhere to the inside of the valves and cause a malfunction. Refer to Best Pneumatics No.5 for further details on compressed air quality. Applicable fluid For Air For Water For Oil For Heated water For High temperature oil Air Air/Water Air/Water/Oil Air(up to 99°C)/Water/Heated water Air(up to 99°C)/Water/High temperature oil Selection Warning 1. Minimum operating pressure differential Be aware that even if the pressure difference is above the minimum operating pressure differential when the valve is closed, the pressure difference may fall below the minimum operating pressure differential when the valve opens, depending on the capacity of the supply source (pumps, compressors, etc.,) or the type of pipe restrictions (the piping is bent continuously due to elbow or tee, or narrow tube nozzle is installed in the end). If the product is used below the minimum operating pressure, the operation becomes unstable, which might cause valve opening or closing failure, or oscillation, leading to failure due to insufficient pressure differential. Select an appropriate valve size with reference to the flow-rate characteristics and flow-rate characteristics table (on pages 140 through to 146). 147 VX2 VXK VXD VXZ VXS VXE VXP VXR VXH VXF2 VX3 VXA