Electric Actuator - STX Range | Bernard Controls | Philippopoulos s.a.
Electric Actuator - STX Range | Bernard Controls | Philippopoulos s.a.

Electric Actuator - STX Range | Bernard Controls

Bernard Controls STX Electric Explosion-Proof Actuator

The STX series comprises multi-turn electric actuators certified for Ex d / NEMA 7 hazardous areas, suitable for gate, globe, and multi-turn valve applications. For quarter-turn service (ball, butterfly, or plug valves), the actuator is paired with a gearbox. Direct mount torque range is 25–2,200 Nm; with gearbox, up to 25,000 Nm for multi-turn, and 200–800 Nm direct or up to 500,000 Nm with gearbox for quarter-turn operation.

Certifications & Environmental Ratings

  • ATEX / IECEx: Ex d IIB T4 standard, options for T5/T6 and IIC.
  • CSA C/US: NEMA 7 / NEMA 9, Class I Groups C,D; Class II Groups E,F,G.
  • IP68 10 m / 96 h, NEMA 6 ingress protection.
  • Temperature: -20 to +70 °C for IIB, -60 to +70 °C optional, -20 to +60 °C for IIC.
  • Corrosion protection C3 per ISO 12944; special coatings for marine or corrosive environments.

Operation & Control

STX supports On-Off (Class A), Inching/Positioning (Class B), and Modulating (Class C) per EN 15714-2. Motor is TENV asynchronous, Class F, with thermal protection. Duty cycle for on-off/positioning: S4 30%, up to 360 starts/hour; for modulating: S4 50%, up to 1,200 starts/hour.

INTELLI+ and Feedback

INTELLI+ version includes integrated reversing starters, display, position and torque sensors. Torque adjustable from 40–100% in 1% increments. Supports 10–250 V AC/DC commands, dry contacts, signaling relays, fault relay, positioner (4–20 mA / 0–10 V), Profibus, Modbus, Foundation Fieldbus, and HART.

Applications

Used in oil & gas units, chemical plants, steam networks, process water, fuel gas systems, and any area requiring explosion-proof certification. Selection is based on torque, number of turns, travel time, Ex zone, supply voltage, and feedback requirements.

FAQ

When is STX selected over ST?
When ATEX, IECEx, or NEMA 7/9 protection is required at the installation site.

What is checked during maintenance?
Ex cable glands, grounding, IP sealing, position limits, torque settings, handwheel, alarm history, and signals to PLC/DCS.

Datasheet and documents

Description

PRODUCT SPECIFICATIONS

TORQUE RANGE

  • 25 to 2,200 Nm (direct)
  • Up to 20,000 Nm on request

COMPLIANCE WITH INTERNATIONAL EXPLOSION-PROOF STANDARDS: ATEX, INMETRO, IEC-EX, EAC-EX, NEMA 7 & 9...

TYPE OF CONTROLS:

  • Electromechanical SWITCH
  • Hardwired
  • Smart INTELLI+® (v2)
  • SIL2

BC DUTY & MODULATING CLASSIFICATION:

  • On-Off: Class A+
  • Inching / Positioning: Class B+
  • Modulating: Class III

ENVIRONMENT: IP 68 / C3 UP TO C5-M / T: -20°C ...+70°C (OPTION LOW T: -60°C)

SPECIAL CONFIGURATIONS: CORROSION PROTECTION, FIRE PROOFING, EXTREME TEMPERATURES

PRODUCT BENEFITS

  • Wide range of speeds / up to 190 rpm according to the model
  • Wide range of number of turns: from a few to 1000 or more
  • Asynchronous motor with high starting torque & S4 Service duty
  • Gears are self-locking at all speed
  • Precise torque measurement and limitation

          > Easy setting with a simple screwdriver

          > Between 40 and 100% of maximum torque value

          > Frictionless system for high precision and repeatability

  • Innovative emergency handwheel system:

          > Non-rotative handwheel with electric motor priority

          > Exclusive handwheel differential system without declutch lever

  • INTELLI+® integrated control available: advanced control solution for your critical applications
  • Double sealing
  • Partial stroke test (PST) included
  • Programmable timer
  • Separated control box & LCS available
  • Wide range of fieldbus available
  • SIL certification as an option

Accessories & Compatibility