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Adjustment valve debugging 1. Trachea connection There are two trachea connections: One is the air supply interface, marked with "SUP" air supply, and the other is the positioner output interface, marked with "OUT" (output). When connecting the air pipe, be careful not to let sealing tape or dirt enter the pipe. The trachea can use φ6mm or φ8mm copper tube. The positioner is generally equipped with a φ6mm ferrule type air pipe joint when it leaves the factory. If you need to use φ8mm copper pipe, please specify when ordering. 2. Circuit connection 1) Remove the cover of the junction box, connect the positive and negative poles of the input signal line to the positive and negative poles of the junction box, and fix them firmly without loosening. 2) The explosion-proof positioner should ensure that the creepage distance between the two wires is ≥4mm. The signal inlet can be connected with an explosion-proof flexible hose. The interface thread is G1/2. The thread length is ≥22. It can also be connected directly with a cable. The outer diameter of the cable is φ8±1mm and the cross-sectional area of the wire is >1.5mm2. The sealing plug and gasket should not be removed at the cable introduction part. The compression nut must be tightened to ensure a tight seal. After modification, tighten the locking screw. 3) The intrinsically safe positioner must be used in conjunction with the safety barrier of the associated equipment. The installation and debugging of the safety barrier must be strictly in accordance with the instructions of the safety barrier. The highest distributed capacitance of connecting wires or cables is <0.03uF, and the highest distributed inductance is <1.0mH. Its wiring diagram is as follows: 3. Precautions: ①Open the cover after cutting off the power supply. ②The case is grounded. ③Safety regulations for explosion-proof electrical equipment must be followed on site. ④Explosion-proof external wiring joints should comply with dIICT explosion-proof level requirements. ⑤Intrinsically safe external wiring connectors should meet the requirements of iaIICT5 explosion-proof level. ⑥The allowed distributed capacitance and inductance values of the connecting wires and cables between the safety barrier and the positioner must be greater than 0.03uF and 1.0mH. ⑦The cross-sectional area of the intrinsically safe cable core wire is S>0.5mm2, and the shielding layer is grounded in a safe place. ⑧The installation and debugging of the safety barrier must comply with the relevant provisions of the safety barrier instruction manual. Adjustment When the positioner is newly installed on the control valve, or the stroke of the control valve does not meet the requirements of the input control signal, it needs to be adjusted. The method is as follows: 1) The air supply pipeline is connected to the actuator through a pressure reducing valve. Use the pressure reducing valve to adjust the air supply pressure so that the actuator stem is located at the center of the stroke. 2) Then, check whether the positioner is at 90° to the feedback lever. Please refer to the "Installation" chapter. 3) Disassemble the air supply pipeline from the actuator, connect it to the air supply interface (SUP) of the positioner, and connect the output interface (OUT) of the positioner to the air chamber of the actuator. 4) The zero point adjustment steps are as follows:: Input a 4mA signal to start the actuator (standard input signal 4-20mA), adjust the zero point adjustment handwheel to make the zero point meet the requirements. 5) The measurement range is adjusted as follows:: Input a 20mA signal and record the valve's stroke. If the stroke is less than the rated range, loosen the range adjustment locking screw, rotate the range adjustment handwheel to move the screw in the direction of the arrow, and then secure the locking screw after adjustment. 6) Repeat steps 4) and 5) above to make the range and zero point reach the specified values. Interchange of positioner forward and reaction types. Interchange steps for linear positioner action types and other characteristics of positioners. The installation position of the positioner range adjustment mechanism depends on the action type of the actuator. Figure II shows the assembly position of the range adjustment mechanism installed on the reaction actuator. For direct-acting actuators, the range adjustment mechanism must be installed on the "direct-acting actuator installation", that is, the range adjustment mechanism shown in Figure II is reversed. The installation direction is as shown by the arrow in Figure II. The downward arrow indicates the forward action type, and the upward arrow indicates the reaction type. The steps to change the installation position of the range adjustment mechanism are as follows:: First, use needle nose pliers or tweezers to remove the feedback spring connection part on the side of the bezel from the spring bolt. Secondly, loosen the mounting bolts and remove the maximum adjustment mechanism. To install the range adjustment mechanism, simply reverse the above steps.