Samson positioner, and the common ones are 3730 series, etc. The following is its related introduction:
Common models
3730-0: electro-pneumatic positioner.
3730-1: electro-pneumatic positioner.
3730-2: electro-pneumatic positioner, starting to include full-function parameterization and advanced diagnosis.
3730-3: electro-pneumatic positioner with HART communication.
3730-4: electro-pneumatic positioner with Profibus.
3730-5: electro-pneumatic positioner with FF.
3730-6: electro-pneumatic positioner with HART, which is an upgraded version of 3730-3, with pressure sensors for monitoring supply and output pressures.
3731-3: explosion-proof electro-pneumatic positioner with HART.
3731-5: explosion-proof electric pneumatic positioner with FF.
Input and output signals: input control signal is 4-20mA, two-wire, with reverse protection, small range 4mA, static damage limit 100mA, small current 3.6mA.
Gas source requirements: gas source pressure is 1.4-7bar.
Environmental adaptability: ambient temperature range is -20℃ to +80℃, protection level reaches IP66.
Appearance and material: die-cast aluminum or stainless steel housing, weight about 1.0kg.
Functional characteristics
- Double-acting actuators can be connected using 3710 reversing amplifier.
- Integrated control valve EXPERTplus diagnostic function.
- Simple single-knob, menu-driven operation, and rotatable reading direction, easy to read in any installation position.
- There are four different initialization modes, which can be started automatically, and there is also an alternative initialization mode, which allows the positioner to start in an emergency without changing the valve position.
- Two-wire system with a small electrical load of 410Ω, adjustable tight closing function, and automatic zero point monitoring.
- Integrated temperature sensor and operating hours counter, which can send condensed status information in accordance with NAMUR recommendation NE 107 through fault alarm contacts or optional analog position transmitter.
Function and working principle
Function: The valve positioner can increase the output power of the control valve, reduce the transmission lag of the control signal, speed up the movement speed of the valve stem, improve the linearity of the valve, overcome the friction of the valve stem and eliminate the influence of unbalanced forces, thereby ensuring the correct positioning of the control valve.
Working principle: Taking the digital electrical valve positioner as an example, it receives the 4-20mA DC analog signal from the control system or controller, compares it with the valve position signal measured by the sensor, changes the control output according to the deviation and preset algorithm, and performs closed-loop positioning control on the pneumatic actuator/control valve.
Mounting Features
Easy to assemble to linear or quarter-turn pneumatic actuators with SAMSON direct integrated mounting connection, NAMUR flange, and control valves with rod brackets in accordance with IEC 60534-6-1 or quarter-turn pneumatic actuators in accordance with VDI/VDE 3845.