Economical Handling of Compressed Air Using Intelligent Electro-pneumatic Positioners Increases Energy Efficiency
Choosing Positioners Wisely
The good news is that plant operators can dramatically reduce the amount of compressed air consumed by positioners without compromising on other requirements such as control quality, ease of handling, and ruggedness.
Siemens, for example, has the portfolio of positioners with the lowest air consumption. A Sipart PS2 digital positioner has an internal air consumption of just 0.036 Nm3/h, so its yearly figures are: power 33 kWh; costs € 2; CO2 emissions 21 kg. This is a saving of more than 90 percent compared to the average positioner.
Besides its miserly air consumption, the Sipart PS2 offers other advantages including an external non-contact sensor for actuators subject to severe vibration, extensive diagnostic functions, and enormous flexibility when mounting to non-standard actuators.
The latest addition to the Siemens positioner family, the Sitrans VP300, boasts air consumption of 0.095 Nm3/h, an operating temperature range from –40 °C to +85 °C, the simplest possible mounting thanks to an OPOS interface, and a user interface with a graphic display and multiple languages.
In conclusion, modern digital electro-pneumatic positions can provide significant savings on compressed air compared to their traditional counterparts. With the right positioner, cost savings, return on investment, environmental protection, and high-quality control can all be achieved simultaneously.