Features

 Double-sealed Structure: VAHN-TECH uses patented torque measurement system to ensure the overload protection of actuators and indicate the torque variation by LCD. The precise torque value is decided by the electronic signal coverted from the reaction force of motor shaft's thrust transferred by pressure sensor, thus solves the problem of calculating the torque according to the changes of power frequency, voltage and temperature.

 Accurate Torque Measurement: VAHN-TECH uses patented torque measurement system to ensure the overload protection protection of actuators and indicate the torque variation by LCD. THe precise torque value is decided by the electronic signal converted from the reaction force of motor shaft's thrust tansferred by pressure sensor, thus solves the problem of calculation the torque according to the changes of power frequency, voltage and temperature.

 Precise Valve Position Measurement: VT-AVM/VT-AVP range actuator takes advanced hall-effect incremental absolute encoder to measure the valve position. The adoption of non-contact encoder design can avoid the disadvantages of traditional potentiometer, which wears easily and has short life. It increases the reliability and service life of the actuator. The setting range of the of the encoder is 2.5 to 150,000,000 circles. For VT-AVM multi-turn actuator, the output angle resolution of the central axis is 7.5Ëš. For VT-AVP part-turn actuator, the output angle resolution of the central axis is 0.05Ëš.

VT-AVM/VT-AVP range actuator can take the 24-bit optical absolute encoder as option. This kind of encoder uses optical encoder disk to record valve position accurately without battery when the power is off. For VT-AVM multi-turn actuator, the output angle resolution of the central axis is 0.2Ëš with maximum 1024 circles. For VT-AVP part-turn actuator, the output angle resolution of the central axis is 0.02Ëš.

 Non-intrusive Design: The VAHN-TECH VT-AVM/VT-AVP range actuator is constructed with the non-intrusive design. The site setting operation can be accomplished by using an infrared setting tool without removing the electric cover. Consequently, the internal electrical control parts can be protected from the site pollution. The design for local operation discards the traditional moving shafts penetrating the control enclosure and uses the hall magnetic sensor technology to control the actuator.

 Reliable Electronic System: VAHN-TECH actuator’s electronic systems use an advanced 32-bit embedded SOC chip, which not only provides with a strong computing ability. But also integrates multifunctional circuit. It packages all the necessary electronic circuits and parts of electronic components without complex electric wiring, have a high reliability for electronic control.

 High Definition LCD: VAHN-TECH actuators incorporate a unique high-definition liquid crystal display. Large display window with backlight enables user to see valve position, torque and functional status from a long distance.

 Safe and Reliable Protection: VT-AVM/VT-AVP range actuator has powerful self-protection function. When there is any improper or wrong operation from user, the actuator will process self-protection and self-correcting.

 Automatic Phase Correction and Adjustment: With phase sequence discrimination function for power supply, VAHN-TECH actuator will rotate correctly, how the three- phase sequence is. It avoids the damaging of valve and actuator because of wrong wiring.

 Phase Lost Protection: To prevent overheating of three-phase motor when losing phase, the phase lost protection circuit will monitor the three-phase power continuously. If one or more phases are lost, the actuator will block the control from control circuit to motor and trigger an alarm.

 Intelligent Protection during Valve Jams: When actuators are rotating in one direction, such as opening, if the torque in this direction is larger than the set torque, the jam protection will be implemented. Jam protection has two modes. One is the general stop mode, that is when it jams, actuator stops working and displays alarm

 Motor Overheating Protection: VAHN-TECH actuator motors are designed with F class insulation, which can work in extreme environments. The thermal switches embedded in the motor windings of actuators will disconnect the relevant contacts, stop actuators and display alarm signals once the winding temperature is over presetting (132ËšC). Motor overheating protection can be modified via setting program.

 Instantaneous Reversal Protection: When actuators are rotating in one direction, such as opening, if the closing signal is commanded, the internal control circuit will stop for a while before executing closing. This technology decreases the over-current damage to the motor, prolongs the contactor's service life and prevents the mechanical driving devices, such as valve stem, gearboxes damaged by shock.

 Indication and Monitoring Contacts: VAHN-TECH Actuator possesses four (which can be extended to eight) sets of indication contacts with dry contact output. (Nominal capacity is 5A 250VAC or 5A 30VDC). Every set of indication contacts can be set as normal open and normal close according to user's requirement. The user can select 27 kinds of the trigger conditions including full open, full close and protection alarm etc. All the functions of indication contacts can be set easily via software.
Apart from the four sets of indication contacts, the actuator also has a pair of monitoring contacts which can indicate the effectiveness of actuator electrical devices. (Nominal capacity is 8A-250VAC or 8A-30VDC). The monitoring contacts can be triggered at any of the following conditions: Losing phase power, control power failure, selecting local control, and selecting local stop.

 Intelligent Protection during Valve Jams: When actuators are rotating in one direction, such as opening, if the torque in this direction is larger than the set torque, the jam protection will be implemented. Jam protection has two modes. One is the general stop mode, that is when it jams, actuator stops working and displays alarm

 Analogue Folomatic Control (Option): VAHN-TECH actuator Folomatic controller allows actuator to position valve automatically in proportion, according to analogue current or voltage signal. The input proportional signal comes to Folomatic controller through Linear Isolator. The controller converts the proportional signal into valve position signal and compares with current valve position to drive the actuator according the discrepancy. By adjusting the dead zone of Folomatic controller and forbidding running time, valve can avoid reciprocating oscillation.

 Fieldbus Control Function (Option): The interface offered by VAHN-TECH actuator has full compatibility with Fieldbus-Mastering control systems and communication protocol. VAHN-TECH actuator can add the Fieldbus module such as Modbus, Profibus and Foundation.

 Remote Indication of Valve Position: VAHN-TECH actuator's current transmitter can convert the present valve position into 4-20mA current output signal. The smallest corresponding signals can be chosen for full open or full close. At rated voltage, the maximum external impedance is 500 Ω and the linearity of the whole stroke is less than 1%.

 Designed Service Life: At the rated torque of on-off actuator, the minimum service life is 30,000 times open/close/open cycles with assumption of maximum seating torque at stroke end and an average of 1/3 maximum seating torque during stroke. Actuator is stalled 25 times against a solid object to prove its durability.

 Life Test: Standard VT-AVM/VT-AVP life test is based on 10,000 times open/close/open cycles (500,000 output turns) with maximum seating torque at stroke end and an average of 1/3 maximum seating torque during stroke. Actuator is stalled 25 times against a solid object to prove its durability.

 Operating Temperature: Actuators are suitable for operating in 30ËšC to +70ËšC ambient temperature. For hazardous area operation and certification, the temperature range indicated on the certificate shall be followed. For temperature outside this range, please contact us.

 Duty Cycle: Duty cycle of motor covers S2 to S4.

 Vibration: Standard VT-AVM/VT-AVPT range actuator is suitable for the environment where the vibration does not exceed the following standard.

 Equipment Induction: The cumulated vibration is 10-1000MHz frequency range must lower than 1g.

 Impact: Maximum acceleration is 5g.

 Seism: If the valve/actuator system shall be operational during and after the event, the frequency range is 150Hz and acceleration is 2g. If actuator is only required to maintain structural integrity, actuator is suitable for maximum acceleration of 5g. Isolation control should be used or the actuator should be mounted far away from valve and drive by an extension shaft with vibration absorbing couplings in the place where it is excessive equipment induced vibration.

 Noise: Independent tests shown that the noise did not exceed 61dB (A) within 1M distance.