Samson Type 3725 Compact Digital Electropneumatic Positioners
The Samson Type 3725 Digital Electropneumatic Positioner (featured model: Type 3725-001000) is SAMSON AG's compact, highly efficient positioner platform engineered specifically for single-acting linear pneumatic control valves in general process automation, HVAC thermal loops, food & beverage processing, and utility water systems[cite: 12]. Designed to replace conventional mechanical or analog electropneumatic positioners, the Type 3725 features a **one-touch automatic calibration button** and an intuitive backlit LCD screen that displays current valve position, operating status, and diagnostics[cite: 12]. Utilizing advanced microprocessor control, the positioner adjusts output supply air dynamically, achieving minimal steady-state instrument air consumption (<0.06 Nm³/h at 1.4 bar) and exceptional positioning accuracy[cite: 12]. Built with a rugged, UV-resistant polycarbon/aluminum housing rated to **IP66 / NEMA 4X**, the Type 3725 supports versatile mounting options including **NAMUR rib attachment (IEC 60534-6-1)**, direct internal duct connection for **Type 3277 actuators**, and rotary valve brackets[cite: 12]. WE DRIVE HONGKONG LIMITED provides technical sourcing, mounting bracket matching, configuration setup, and global express supply for Samson Type 3725 positioners worldwide[cite: 12].
Technical Specifications
| Featured Model | Type 3725-001000 (Compact Electropneumatic Digital Positioner, 4-20 mA Input, Backlit LCD, Single-Acting, Integrated / NAMUR Mounting)[cite: 12] |
|---|---|
| Brand / Manufacturer | SAMSON AG (German Precision Process Control Engineering)[cite: 12] |
| Product Series | Type 3725 Series Compact Digital Valve Positioner Platform[cite: 12] |
| Control Signal & Electrical Connection | 4 to 20 mA Two-Wire Signal (Minimum Current 3.6 mA); Cable Gland M20x1.5 / 1/2" NPT[cite: 12] |
| Supply Air & Pressure Range | 1.4 bar to 6 bar (20 psi to 90 psi) Clean Instrument Air; Very Low Air Consumption (<0.06 Nm³/h at 1.4 bar)[cite: 12] |
| Stroke / Angle Range | Linear Actuators: 3.75 mm to 50 mm (0.15" to 2.0"); Rotary Actuators: 24° to 100° Opening Angle[cite: 12] |
| Hysteresis & Linearity | Hysteresis ≤ 0.3%; Linearity Error ≤ 0.5%; Insensitive to Mechanical Pipeline Vibration[cite: 12] |
| Enclosure & Ambient Protection | IP66 / NEMA 4X Environmental Rating; Operating Ambient Temperature: -20°C to +70°C (-4°F to +158°F)[cite: 12] |
Documentation & Resources
Samson Type 3725 Model Options & Mounting Kit Matrix
Complete selection matrix for Samson Type 3725 electropneumatic positioners. Review model codes, input options, mounting interfaces, and application suitability[cite: 12]:
| Samson Model Code | Actuator Type & Action | Mounting Interface | Explosion Protection | Display / Setup | Samson Code Summary |
|---|---|---|---|---|---|
| Type 3725-001000 | Single-acting Linear / Rotary | Type 3277 & NAMUR Rib (IEC 60534) | Standard Non-Hazardous | Backlit LCD + Auto Button | 3725-0010000000000[cite: 12] |
| Type 3725-111000 | Single-acting Linear / Rotary | Type 3277 Integrated Mounting | ATEX / IECEx Intrinsic Safety | Backlit LCD + Auto Button | 3725-1110000000000[cite: 12] |
| Mounting Kit (3277) | Direct to Type 3277 Actuator | Internal Air Duct Seal Interface | N/A | Tubing-free installation | 1400-9851 Bracket Kit[cite: 12] |
| Mounting Kit (NAMUR) | NAMUR Rib Yoke / Rod Yoke | IEC 60534-6-1 Standard Clamp | N/A | External tubing required | 1400-1200 Bracket Kit[cite: 12] |
| Mounting Kit (Rotary) | Quarter-turn Rotary Actuators | VDI/VDE 3845 Shaft Interface | N/A | Includes follower arm | 1400-1202 Rotary Kit[cite: 12] |
Analog Positioner to Samson Type 3725 Digital Upgrade Guide
Direct replacement guide for upgrading high-maintenance analog or mechanical valve positioners to the digital Samson Type 3725 platform[cite: 12]:
| Legacy Analog Positioner | Operational & Maintenance Disadvantages | Current Samson Type 3725 Digital Upgrade | Key Calibration & Efficiency Advantages |
|---|---|---|---|
| Analog Mechanical Positioner (No Screen) | Time-consuming manual zero and span screw adjustments prone to vibration drift | Samson Type 3725 Digital Positioner One-Touch Auto-Calibration | Microprocessor automatically detects end stops, optimizes gain parameters, and calibrates stroke in seconds[cite: 12]. |
| High Air Consumption Pneumatic Positioner | Continuous air bleed wastes expensive compressed air in large processing plants | Samson Type 3725 Low-Bleed Design <0.06 Nm³/h Air Bleed | Dynamic internal pneumatic valves cut steady-state air consumption to near zero, reducing compressor operating costs[cite: 12]. |
| Positioner with External Air Tubing Breakes | Tubing mechanical damage, fitting air leaks, and rust under wet washdown conditions | Samson Type 3725 + Type 3277 Actuator Tubing-Free Air Duct | Mounts directly to Type 3277 actuators using internal air ports, eliminating external tubing and air leaks completely[cite: 12]. |
Expert Technical Sourcing & Control Valve Loop Integration Notes
When upgrading valve manifolds or replacing outdated mechanical positioners, switching to Samson Type 3725 positioners delivers immediate operational benefits: one-button automatic calibration, clear digital status display, near-zero steady-state air bleed, high resistance to pipe vibration, and IP66 weatherproofing[cite: 12]. Simply provide us with your existing positioner part number or control valve model details, and our technical engineering team will deliver a 100% compliant replacement specification and proposal[cite: 12].
Core Benchmark Model Standard Configurations
- Type 3725-001000 (Standard Digital)[cite: 12]
- Type 3725-111000 (ATEX Ex ia Digital)[cite: 12]
- Samson 3725 Positioner 4-20mA[cite: 12]
- Samson 3725 Auto-Calibration Unit[cite: 12]
- Samson 3725 Type 3277 Mount Kit[cite: 12]
- Samson 3725 NAMUR Rib Mounting Kit[cite: 12]
- Samson 3725 Rotary Valve Mounting Kit[cite: 12]
- Samson Type 3730 Smart Positioner[cite: 12]
- Samson Type 3730-2 HART Positioner[cite: 12]
- Samson Type 3730-3 Advanced HART[cite: 12]
- Samson Type 3241 Globe Valve Control[cite: 12]
- Samson Type 3277 Diaphragm Actuator[cite: 12]
- Samson Electropneumatic Positioner[cite: 12]
- Samson Linear Valve Positioner[cite: 12]
- Samson Compact Valve Positioner[cite: 12]
- Samson Low Air Consumption Positioner[cite: 12]
- Samson Digital Positioner LCD[cite: 12]
- Samson Control Valve Accessories[cite: 12]
- Samson Positioner Calibration Sourcing[cite: 12]
- WE DRIVE HK Samson Positioner Supplier[cite: 12]
