Abstract
The continuous trend within the factory automation and process control to use intelligent peripheral field devices increasingly leads to an extended function range of proportional pneumatic valves and drives. Typical requests in his area are:
-interfacing to a digital communication system
-line-up support
-diagnostic and service functions
-error messages/alarm
-compatibility/exchangeability
In the area of process control there is a demand to lower the installation costs and to transfer the energy and the control signal via the same wire. For this reason the presented valve is characterised by a reduced electrical power consumption. The pilot control stage operates according to the spool valve principle and reduces the pneumatic power consumption substantially, too. The maximum electrical power consumption of the entire valve including the connection of the field bus and the electrical amplifier stage amounts to less than 1W.
