Air pressure may be used as an alternative signaling medium to electricity. Imagine a pressure transmitter designed to output a variable air pressure according to its calibration rather than a variable electric current. Such a transmitter would have to be supplied with a source of constant-pressure compressed air instead of an electric voltage, and the resulting output signal would be conveyed to the indicator via tubing instead of wires:
Advantages of pneumatic instruments
However, pneumatic instruments actually enjoy some definite technical advantages that ensure their continued use in certain applications even in the 21st century.
- A decisive advantage is the intrinsic safety of pneumatic field instruments. Instruments that do not work with electricity can not generate electrical sparks. This is very important in “classified” industrial environments where there are gases, liquids, powders and explosive dusts.
- The pneumatic instruments also purge themselves. Its continuous purging of compressed air from the ventilation holes in the relays and pneumatic nozzles acts as a natural clean purge for the interior of the instrument, preventing the entry of dust and vapor from the outside with a slight positive pressure inside the box of the instrument.
- Ease of power and speed transmission
- Ease of use
- Ease of maintenance
- Infinite availability of the source ;Air is the most important thing in the pneumatic system, and as we all know, air is available in the world around us in unlimited quantities at all times and places
Types
- Standard Valves
- Miniature Valves
- System Logic Devices
- Cylinders
- Interface Valves
- Accessories
- Commercial Vehicles Applications
