420MD 520MD 1500 3200MD 3400MD 3800 3800E Series

The Flowserve Logix series of digital and electro-pneumatic valve positioners provides high-accuracy valve positioning, advanced diagnostics, and reliable control for process automation. Designed for pneumatic control valves used in continuous and batch operations, the Logix family supports both linear and rotary actuators, enabling flexible integration across oil and gas, chemical, refining, power generation, pulp and paper, water treatment, and industrial manufacturing.

The product line covers a full control range, from legacy analog-digital hybrids to next-generation smart positioners featuring predictive maintenance and extended diagnostics. Whether users require simple electro-pneumatic control, HART digital communication, or high-performance diagnostics, the Flowserve Logix family delivers adaptable solutions for operational reliability and precise valve actuation.

• Supports linear and rotary pneumatic actuators
• Modular product architecture for field serviceability
• Digital control for improved accuracy and repeatability
• HART compatibility on MD and advanced models
• Auto-calibration for quick commissioning
• Extended diagnostics available on advanced variants
• Low air consumption for efficient operation
• Proven reliability in harsh outdoor environments
• Globally recognized for industrial valve automation

• Automated valve control for flow, pressure, and level regulation
• Pipeline valve actuation and tank farm flow control
• Batch and continuous chemical processing
• Steam and utility systems in power generation
• Refining, petrochemical operations, LNG facilities
• Water treatment and wastewater management
• Retrofit upgrades replacing legacy pneumatic positioners

1. When reliability monitoring is required
   Use Logix 3800E or 3400MD
2. When digital accuracy and remote configuration are required
   Use Logix 520MD, 3200MD, 3800
3. When cost-effective modernization is required
   Use Logix 1500 or 420MD

• Stable control under dynamic loads and calibration drift
• Reduced process variability with precision positioning
• Predictive maintenance through digital diagnostics
• Lower maintenance frequency and improved uptime
• Interchangeable modules simplify spare parts strategy
• Long lifecycle with proven field durability

• Mount according to actuator NAMUR standard
• Connect instrument air to supply and actuator ports
• Wire 4–20 mA signal and HART as applicable
• Run auto-tuning for actuator travel control
• Validate valve response for process integration

• Are all Logix models compatible with rotary and linear actuators
  Yes, with correct mounting hardware and linkage kits.
• Which models support predictive diagnostics
  Logix 3800E and selected versions of 3400MD.
• Do legacy models remain available for replacement
  Yes, Logix 1500 and 420MD are commonly used in modernization projects.
• Can a Logix positioner replace a competitor smart positioner
  In most applications, yes. Mounting and stroke alignment must be verified.
• Does the MD family require special software
  MD series supports configuration through HART field tools.

• Flowserve pneumatic actuators
• Flowserve control valves and accessories
• Valve position feedback and limit switch modules
• Smart valve controllers and automation components