New Flowserve Logix 520MD Digital Positioner 520MD+44-W2D100 520MD+44-W2D3FN EAC Certification

The Flowserve Logix 520MD Digital Positioner is a high-performance smart valve positioner designed to accurately control pneumatic control valves in automated process systems. As part of the Logix MD (Modular Digital) family, the 520MD combines advanced control algorithms, field diagnostics, and fast response to ensure stable and reliable process regulation.

The 520MD supports HART digital communication, making it suitable for remote monitoring, parameter adjustment, commissioning, and preventive maintenance. With compatibility for both linear and rotary pneumatic actuators, the Logix 520MD is commonly used in oil and gas, chemical processing, refining, power generation, paper mills, and general industrial manufacturing.

• Smart digital valve positioning with accurate travel control
• Supports 4–20 mA input with HART communication
• Compatible with linear and rotary pneumatic actuators
• Auto-tuning and auto-calibration for simplified setup
• Advanced diagnostics enable predictive maintenance
• Fast response with stable control under dynamic load conditions
• Modular design for flexible configuration and field serviceability
• Low air consumption improves efficiency and reduces operating cost
• Field-proven performance in continuous process operations
• Reliable control suitable for throttling and on-off applications

Specifications vary based on configuration and actuator type.

The Flowserve Logix 520MD receives a 4–20 mA command signal from the process control system. Its internal electronics compare the command with valve position feedback and modulate pneumatic output to move the actuator to the required position. Through HART communication, field technicians can perform configuration, tuning, diagnostics, and remote troubleshooting without removing the device from service.

• Automated flow and pressure control on industrial valves
• Oil and gas upstream and midstream valve automation
• Chemical and petrochemical batch and continuous processes
• Steam and utility systems in power plants
• Refining and pipeline pressure regulation
• Process tank level control using valve modulation
• Modernization projects upgrading analog positioners to smart models

• Improved control valve accuracy and repeatability
• Predictive maintenance enabled through digital diagnostics
• Reduced downtime and lifecycle cost
• Less manual intervention due to auto-calibration
• Optimized energy use with efficient air management
• Rugged design for long-term field operation
• Faster system startup and configuration

• Mount the positioner to the actuator according to NAMUR standards
• Connect air supply and tubing to actuator ports
• Wire the 4–20 mA signal and HART communication leads
• Run auto-calibration for travel and position feedback
• Verify response and valve movement under process conditions

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