Technical Specifications:

• Actuator Stroke: 16 mm (0.63 inch)
• Actuator Type: Single-acting (spring-return)
• Input Signal: 4–20 mA DC (2-wire)
• Supply Air Pressure: 1.4 to 7.0 bar (20 to 100 psi)
• Output Pressure Range: 0.2 to 1.0 bar (3 to 15 psi)
• Communication Protocol: HART 7 / HART 5
• Ambient Temperature: -40°C to +80°C (-40°F to +176°F)
• Protection Rating: IP66 / IP67 (NEMA 4X)
• Housing Material: Aluminum alloy die-cast with epoxy coating
• Weight: Approximately 2.8 kg (6.2 lbs)
• Approvals: ATEX, IECEx, SIL 2 (IEC 61508)

Functional Features:

• Auto-calibration function with single-push initialization
• Built-in diagnostic and alarm functions (stroke deviation, air supply failure, signal loss)
• HART digital communication for remote configuration and diagnostics
• Linear, equal percentage, and quick-opening flow characterizer built-in
• Built-in positioner feedback sensor (LVDT type)

Structural Features:

• Robust aluminum alloy housing resistant to corrosion and impact
• IP66/IP67 sealed enclosure suitable for outdoor and hazardous area installation
• DIN mount bracket for standard actuator mounting
• Large LCD display (on some variants) or LED status indicators

Working Principle:
The positioner receives a 4–20 mA current signal from the DCS/PLC. The internal microprocessor compares the commanded position with the actual valve stem position (measured by an LVDT sensor). The error signal is processed through a PID controller, which modulates the pneumatic output pressure to the actuator diaphragm, driving the valve to the correct position. HART communication allows bidirectional digital data exchange over the same 4–20 mA loop.

Advantages & Highlights:

• HART 7 protocol enables advanced diagnostics and remote configuration without interrupting the control signal
• SIL 2 certified for safety-instrumented applications
• Auto-calibration reduces commissioning time significantly
• Wide ambient temperature range of -40°C to +80°C
• Spring-return fail-safe design ensures valve returns to safe position on signal loss

Applicable Industries:

• Oil and gas (upstream, midstream, downstream)
• Petrochemical and refinery
• Power generation (steam, gas turbine)
• Pulp and paper
• Pharmaceutical

Installation Requirements:

• Mount directly on the pneumatic actuator per IEC 60534-6-1
• Ensure air supply line is clean, dry, and filtered (5 μm filter recommended)
• Cable entry via approved cable glands (Ex-rated for hazardous areas)
• Maintain minimum 300 mm clearance around the positioner for maintenance access

Usage Precautions:

• Never exceed the maximum supply pressure of 7.0 bar (100 psi)
• Use only Yokogawa-specified mounting hardware
• In hazardous areas, install only with proper Ex-certified enclosures and barriers
• Perform zero and span calibration after initial installation and annually thereafter
• Do not disassemble the housing in explosive atmospheres