3、 Adjustment and wiring method of worm gear transmission device of signal butterfly valve
1. Open the cover of the electrical switch box, connect the core wire of the cable to the corresponding terminal according to the electrical control requirements, seal the cable inlet, and fix the cable at the same time to prevent damage to the cable wiring when the external force affects.
2. When the valve is in the "fully closed" position, turn the lower closing cam clockwise, so that the cam just touches the microswitch (you can hear a click), and then tighten the screw on the cam to fix the cam.
3. When the valve is in the "full open" position, turn the upper open cam counterclockwise and adjust the open cam in the same way as above.
4. Adjust the limit screw. When the valve is in the "fully closed" or "fully open" position, the limit screw should not be just against the limit plane of the worm gear, but should have a certain clearance, and then tighten the lock nut on the limit screw.
5. Cover the electrical switch box cover. When the valve is in the "fully closed" position, make the pointer of the opening indicator point to the "0" scale on the dial, and tighten the screws to fix the pointer.

Of course, like the positioning scheme of the pneumatic control valve, a positioning valve and a two position three-way solenoid valve can be installed between the positioner and the actuator. When the air is cut off, the positioning valve can be used to maintain the position, and when the signal is cut off, the solenoid valve can be used to maintain the position. However, the solenoid valve and positioner shall be interlocked.