SAMSON 3725-11 Intrinsically Safe Electro pneumatic Valve Positioner
The SAMSON 3725-11 Electropneumatic Valve Positioner is designed for accurate positioning and automated control of single-acting pneumatic valve actuators in industrial process systems.
- Two-Wire Wiring Configuration
- 1.4–7 Bar Standard Supply Air Pressure
- 4–11.9 mA or 12.1–20 mA Split-Range Operation
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- Fast dispatchAustralia & worldwide
- Technical supportTalk to an engineer
- 1 Year Warranty
Product Overview
The SAMSON 3725-11 Electropneumatic Valve Positioner is designed for accurate positioning and automated control of single-acting pneumatic valve actuators in industrial process systems. Manufactured by SAMSON, this compact positioner uses a 4–20 mA electrical control signal to regulate pneumatic output pressure and maintain the required valve position. Its microprocessor-based control system continuously compares the input signal with actual valve travel, automatically adjusting the pneumatic output to support accurate positioning, stable flow regulation, and dependable industrial operation.
Part of the SAMSON Type 3725 series, the 3725-11 belongs to the intrinsically safe positioner family intended for appropriately certified hazardous-area installations. It features automatic initialization, non-contact position sensing, an integrated LCD, and three capacitive operating keys for convenient local configuration. Its compact, IP66-rated housing supports installation on compatible SAMSON Type 3277 and Type 3372 actuators, as well as linear and rotary pneumatic actuators using suitable mounting accessories. The positioner is suitable for oil and gas processing, chemical manufacturing, power generation, water treatment, and industrial automation applications.
Technical Specifications
|
Specification |
Value |
|---|---|
|
Product Name |
Electropneumatic Valve Positioner |
|
Manufacturer / Brand |
SAMSON |
|
Main Model |
3725-11 |
|
Series |
Type 3725 |
|
Product Type |
Electropneumatic Valve Positioner |
|
Control Technology |
Microprocessor-Based Electropneumatic Control |
|
Electrical Input Signal |
4–20 mA DC |
|
Wiring Configuration |
Two-Wire |
|
Communication Protocol |
Analogue Input, Without HART |
|
Actuator Configuration |
Single Acting |
|
Actuator Compatibility |
Pneumatic Linear and Rotary Actuators |
|
Operating Principle |
Electronic Position Control with Pneumatic Output |
|
I/P Conversion |
Integrated Analogue I/P Converter |
|
Position Measurement |
Non-Contact Magnetoresistive Sensor |
|
Calibration |
Automatic Initialization |
|
Local User Interface |
LCD Display and Three Capacitive Keys |
|
Explosion Protection Family |
Intrinsically Safe |
|
ATEX Protection, Certified Version |
Ex ia IIC T4 Gb |
|
Standard Supply Air Pressure |
1.4–7 Bar |
|
Pneumatic Output Pressure |
0 Bar up to Supply Pressure |
|
Adjustable Output Pressure Limit |
Approximately 2.3 Bar |
|
Direct Attachment Travel, Type 3277 |
5–30 mm |
|
Type 3372 Actuator Travel |
15 or 30 mm |
|
NAMUR Attachment Travel |
5–50 mm |
|
Rotary Operating Angle |
24–100° |
|
Split-Range Operation |
4–11.9 mA or 12.1–20 mA |
|
Hysteresis |
≤0.3% |
|
Sensitivity |
≤0.1% |
|
Direction of Action |
Reversible |
|
Valve Characteristics |
Three Globe Valve and Nine Rotary Valve Characteristics |
|
Housing Material |
Polyphthalamide (PPA) |
|
Display Window Material |
Polycarbonate |
|
External Metal Components |
Stainless Steel |
|
Enclosure Protection |
IP66 |
|
Electrical Cable Gland |
M20 × 1.5 |
|
Pneumatic Connection Options |
G 1/4 or 1/4 NPT |
|
Standard Ambient Temperature |
−20°C to +80°C |
|
Approximate Weight |
0.5 kg |
|
Instrument Air Requirements |
Clean, Dry Instrument Air |
|
Related Model |
3725-00 |
|
Related Positioners |
4763-01100121, 4763-01200121 |
|
Related Converter Family |
SAMSON Type 6109 |
|
Condition |
New |
|
Warranty |
1 Year |
Key Features
Intrinsically safe electropneumatic valve positioning for suitably certified hazardous-area applications
Standard 4–20 mA DC electrical input for industrial process control systems
Two-wire electrical configuration for straightforward control system integration
Single-acting pneumatic output for compatible control valve actuators
Microprocessor-based positioning technology for accurate valve travel control
Integrated I/P converter for converting electrical signals into pneumatic pressure
Automatic initialization for simplified installation and commissioning
Non-contact magnetoresistive position sensing for reliable valve travel measurement
Integrated LCD display for local monitoring and configuration
Three capacitive operating keys for convenient parameter adjustment
Compact polyphthalamide housing for industrial instrumentation installations
IP66 enclosure protection against dust and water ingress
Reversible operating direction for compatible valve control arrangements
Split-range operation for applications requiring multiple control valves
Adjustable pneumatic output pressure limit for compatible actuator requirements
Direct mounting compatibility with selected SAMSON Type 3277 actuators
NAMUR mounting capability for compatible linear control valve actuators
VDI/VDE 3845 mounting support for rotary pneumatic actuators
Integrated diagnostic and continuous zero-point monitoring functions
Suitable for industrial control valve maintenance, replacement, and automation upgrades
Typical Applications
Industrial pneumatic control valve positioning
Oil and gas production and processing facilities
Chemical and petrochemical manufacturing plants
Petroleum refining and processing installations
Power generation and utility systems
Water and wastewater treatment facilities
Industrial manufacturing and production machinery
Single-acting pneumatic actuator control systems
Linear globe valve positioning
Rotary ball and butterfly valve automation
Industrial flow and pressure regulation systems
Temperature control and heat exchanger applications
Hazardous-area valve instrumentation with appropriate certification
Distributed control systems using 4–20 mA analogue signals
Industrial valve maintenance and equipment replacement
Shipping & Support
Fast dispatch – Australia & Worldwide Shipping
Technical assistance available
1-year warranty
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