Overview
Positional control or proportional valve positioning systems are available using either a pneumatic impulse signal (e.g. 0.2 to 1 Barg) or an electrical signal (normally 4 to 20 mA). These systems are designed either to have customer defined pre-set positions or to have full control of the valve between the open and closed positions. Valve positioning systems can be used in conjunction with on/off production or ESD controls and can be utilised for a partial test system e.g. using digital controllers. PLC controllers can also be incorporated to provide complete automatic valve positioning control via input from pressure transmitters.
Applications
Precise positioning of quarter-turn and linear valves.
Operating Ranges
Electrical Supply (VAC)
- 380/440V – 3 Phase – 50/60 Cycles
- 110/240V – Single Phase 50/60 Cycles
Electrical Supply (VDC)
- 24VDC 50W or 100W
Communications
- Command signal: 4-20mA
- Re-transmission Signal: 4-20mA
- Protocol: 4-20mA HART or Foundation Fieldbus
Accuracy
- Positional: Better than ±0.5%
- Repeatability: Better than ±0.5%
Temperatures
- Low: -60 to +60°C (-76 to +140°F)
- Standard: -20 to +60°C (-4 to +140°F)
Key Features & Benefits
- The same simplicity and low cost of installation as provided by electric actuators
- Fail safe or fail last operation
- The power, precision and compact size of high pressure hydraulic systems
- Industry-leading control options and system diagnostics
- Zero emissions
- Environmentally responsible via low power, solar powered and biodegradable fluid options