Meta Description & Product Overview
The Foxboro SRD991 Intelligent Valve Positioner is a state-of-the-art digital positioner designed for high-precision control of both linear and rotary actuators. Engineered by Schneider Electric (formerly Invensys Foxboro), this positioner supports HART® 7 and Foundation Fieldbus™ protocols, delivering advanced valve diagnostics, automatic calibration, and reliable performance in harsh environments. With its explosion-proof design and IP66 protection rating, the SRD991 is ideal for critical process control applications in industries such as oil & gas, power, chemicals, and water treatment.
Key Features
- Digital Communication: Supports HART 5/6/7 and Foundation Fieldbus for seamless integration
- Precise Valve Control: Exceptional linearity (±0.2%) and repeatability (±0.1%)
- Built-in Diagnostics: Monitors valve health, actuator friction, air pressure, and more
- Auto Calibration: One-touch setup simplifies commissioning and tuning
- Explosion-Proof Certified: ATEX, FM, CSA, and IECEx approvals for hazardous locations
- LCD Display Interface: Multilingual user interface for local configuration
- Rugged Construction: IP66-rated aluminum housing with corrosion-resistant coating
- Universal Mounting: Compatible with a wide range of linear and rotary actuators
Technical Specifications
| Parameter |
Specification |
| Input Signal |
4–20 mA with HART® communication |
| Communication Protocols |
HART 5/6/7, Foundation Fieldbus |
| Supply Pressure |
1.4 to 6.9 bar (20 to 100 psi) |
| Positioning Accuracy |
≤ ±0.2% linearity |
| Repeatability |
≤ ±0.1% |
| Response Time |
≤ 100 ms |
| Mounting Type |
Linear and rotary actuators (NAMUR interface) |
| Display |
LCD screen with push-button control |
| Diagnostics |
Valve friction, air leakage, deviation monitoring |
| Material |
Anodized aluminum housing |
| Protection Rating |
IP66 / NEMA 4X |
| Operating Temperature |
–40 °C to +85 °C |
| Explosion-Proof Certifications |
ATEX, IECEx, FM, CSA (Zone 1 / Div 1) |
