SAMSON 3725-00 Electro pneumatic Valve Positioner 4–20 mA
The SAMSON 3725-00 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 (20–105 psi) Instrument Air Supply 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 3725-00 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 standard 4–20 mA DC electrical control signal to regulate pneumatic output pressure and maintain the required valve position. Its microprocessor-based control system continuously compares the requested valve position with actual actuator travel, automatically adjusting the pneumatic output to deliver stable flow regulation, accurate valve positioning, and reliable industrial performance.
Part of the SAMSON Type 3725 series, the 3725-00 features automatic initialization, non-contact magnetoresistive position sensing, an integrated LCD display, and three capacitive operating keys for convenient configuration. Its durable polyphthalamide housing provides IP66 protection, while its compact construction supports direct installation on compatible SAMSON Type 3277 and Type 3372 actuators. The positioner also supports NAMUR mounting on linear actuators and VDI/VDE 3845 mounting on rotary actuators. Designed for conventional analogue control systems, it is suitable for chemical processing, water treatment, power generation, industrial manufacturing, and pneumatic control valve automation.
Technical Specifications
|
Specification |
Value |
|---|---|
|
Product Name |
Electropneumatic Valve Positioner |
|
Manufacturer / Brand |
SAMSON |
|
Main Model |
3725-00 |
|
Product 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 |
|
Pneumatic Amplification |
Integrated Air Capacity Booster |
|
Position Measurement |
Non-Contact Magnetoresistive Sensor |
|
Calibration |
Automatic Initialization |
|
Local User Interface |
LCD Display and Three Capacitive Keys |
|
Explosion Protection |
Without Explosion Protection |
|
Instrument Air Supply Pressure |
1.4–7 Bar (20–105 psi) |
|
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 |
|
Air Consumption |
≤100 lₙ/h under Specified Test Conditions |
|
Actuator Supply Air Capacity |
8.5 m³ₙ/h at Δp = 6 Bar |
|
Actuator Exhaust Air Capacity |
14.0 m³ₙ/h at Δp = 6 Bar |
|
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 with Suitable Connecting Rail |
|
Standard Ambient Temperature |
−20°C to +80°C |
|
Approximate Weight |
0.5 kg |
|
Instrument Air Requirements |
Clean, Dry Instrument Air |
|
Related Model |
3725-11 |
|
Condition |
New |
|
Warranty |
1 Year |
Key Features
Electropneumatic valve positioning for accurate industrial process control
Standard 4–20 mA DC electrical input for conventional industrial automation systems
Two-wire electrical configuration for straightforward control system integration
Single-acting pneumatic output for compatible valve actuators
Microprocessor-based control technology for accurate valve travel regulation
Integrated I/P converter for electrical-to-pneumatic signal conversion
Automatic initialization for simplified installation and commissioning
Non-contact magnetoresistive position sensing for reliable actuator travel measurement
Integrated LCD display for convenient local monitoring and configuration
Three capacitive operating keys for straightforward parameter adjustment
Compact polyphthalamide housing designed for industrial instrumentation applications
IP66 enclosure protection against dust and water ingress
Instrument air supply pressure range of 1.4–7 bar
Reversible operating direction for compatible valve control arrangements
Split-range operation for suitable process control applications
Adjustable pneumatic output pressure limit for matching actuator requirements
Direct mounting compatibility with suitable SAMSON Type 3277 actuators
Supports installation on compatible SAMSON Type 3372 actuators
NAMUR mounting capability for linear pneumatic actuators
VDI/VDE 3845 mounting compatibility for rotary pneumatic actuators
Continuous zero-point monitoring for maintaining positioning performance
Configurable tight-closing function for compatible valve applications
Suitable for industrial control valve maintenance, replacement, and automation upgrades
Typical Applications
Industrial pneumatic control valve positioning
Single-acting pneumatic actuator control systems
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
Linear globe valve positioning
Rotary ball and butterfly valve automation
Industrial flow and pressure regulation systems
Temperature control and heat exchanger applications
Conventional 4–20 mA process control loops
SAMSON Type 3277 pneumatic actuator installations
SAMSON Type 3372 actuator control systems
Industrial valve instrumentation maintenance
Process automation equipment replacement and refurbishment
Shipping & Support
Fast dispatch – Australia & Worldwide Shipping
Technical assistance available
1-year warranty
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