C&K South - OEM Products

Limitorque Valve Actuators

QX Electronic Valve Actuator

The Limitorque QX is the entry into the quarter-turn, non-intrusive, double-sealed, smart electronic actuator marketplace. The QX design builds on more than 15 years of proven MX technology to provide all the user-preferred features in a quarter-turn smart actuator package. What sets the QX quarter-turn actuator apart is the combination of control and reliability integrated by advanced Limitorque technology. An innovative handwheel parallel to the LCD screen permits the actuator to be installed in areas with limited space and eases manual setup and operation routines. The LCD screen also provides local actuator control as well as calibration and diagnostic information including motor voltage, identification, and hardware and software data.

Features and Benefits


  • Network options include Modbus® DDC, Foundation Fieldbus™ H1, PROFIBUS DP™ V1, PROFIBUS PA™, DeviceNet™, and HART®. Pioneered by the innovative absolute encoder first introduced on the MX, the QX actuator features an absolute encoder for positioning which doesn't require troublesome batteries and is designed with B.I.S.T. (Built In Self-Test) capability for self-diagnosis.

  • Employs an advanced brushless DC (BLDC) motor which eliminates sparks, reduces mechanical and electrical noise, and dissipates heat better than brushed DCV motors. BLDC motors are noted for endurance and accurate positioning and also permit connection of a global range of voltages (single-phase and three-phase ACV and 24-48 DCV) without modification to the actuator.

  • Additional features of the QX include LimiGard circuitry, which safeguards the actuator from spurious electromagnetic interference, 100% solid state controls, and Limitorque’s namesake feature – torque sensing.


Common Applications

Sewage Collection and Treatment, Tank Farm Transfer, Water Supply and Distribution (water), Boiler Circulation, Decoking, Petroleum Production and Refining, Filtration, Nuclear Service, Gas Production, Heavy Oil, Oil Sands and Shale, Molten Salt Transfer, Desalination