Proportional pressure regulators for multiple selectable pressure ranges
Proportional valves
Unique: cascade control with integrated multi-sensor control
Only the proportional valves VPPM from Festo have this intelligent control technology with integrated sensors. Multi-sensor control is based on the advanced concept of cascade control. It is characterised by having several control circuits that are nested inside each other, in contrast to conventional direct-action controllers. The overall system is thus subdivided into smaller task-specific sub-systems that are easier to control. The significant benefit is that both diaphragm pressure in the valve and output pressure are monitored.
This leads to an extremely stable and accurate control response, even in demanding applications.
Conventional control circuit
Control circuit with multi-sensor control: cascade control
Control circuit with multi-sensor control: cascade control
The two-stage control circuit provides stable control, without overshooting.
The multi-sensor control is based on a cascade control system. Multiple control circuits are nested inside each other, and the total controlled system is subdivided into smaller, more effectively controlled partial systems. This increases control precision several times over when compared with a direct-acting controller.
Advantages:
- Better control precision and dynamic response than isolated direct-action controllers
- Optimum small signal characteristics without overshooting
- Precise control even over long distances
- Insensitive to temperature changes
Pressure (bar)/ Time (s)
| Setpoint pressure | ||
| Characteristic working pressure curve for “individual controller” | ||
| Characteristic working pressure curve for “cascade controller” |