Fisher Valve Positioner   Fisher Positioner Wholesale

 

PRODUCT DESCRIPTION

The Fisher Valve Positioner instrument allows for your operation to run closer to setpoint, improving product quality with more accurate control. Using FIELDVUE Performance Diagnostics, valve operation is monitored online to evaluate performance and reliability. 

The FIELDVUE DVC6200 digital valve controller is a HART communicating instrument that converts a two‐wire 4‐20 mA control signal into a pneumatic output to an actuator. It can easily be retrofitted in place of existing analog positioners on most Fisher and non‐Fisher pneumatic actuators.

 

Features of Fisher Valve Positioner

The high performance, linkage-less feedback system eliminates physical contact, which eliminates wearing on parts.

The fully encapsulated electronics resist the effects of vibration, temperature, and corrosive atmospheres.

Provides quick responsiveness to large step changes and precise control for small setpoint changes.

The DVC6200 is a HART communicating device, so information can be accessed anywhere along the loop. This flexibility can reduce exposure to hazardous environments and make it easier to evaluate valves in hard to reach locations.

The modular design allows critical working components to be replaced without removing field wiring or pneumatic tubing.

When installed in an integrated control system, significant hardware and installation cost savings can be achieved.

The self-diagnostic capability provides valve performance and health evaluation.

Digital communication provides easy access to the condition of the valve.

 

Fisher Valve Positioner should be considered in the following situations:

1. When precise valve positioning is required;

2. When it is necessary to speed up the valve response. Positioners use higher pressure and greater airflow to adjust valve position;

3. Increase the pressure that specific actuators and valves can close (acting as an amplifier);

4. Over 5 bar for single seat valve or over 10 bar for double seat valve when the pressure of the valve drops at maximum working flow;

5. Linearize the nonlinear actuator;

6. Different pressure differences in the fluid will cause the position of the plug to change;

7. During wide throttling range control;

8. When the valve handles suspended sludge or solids.

You can provide your detailed parameters, and we will choose the most suitable Fisher Valve Positioner for you.

 

How To Calibrate the Fisher Valve Positioner

Step 1. Close the fisher valve positioner supply pressure. Connect or reconnect from valve positioner output to the actuator pipes necessary for power connection. The input connected to the valve positioner and the input signal value is set in the middle range.

Step 2. Mobile baffle components into the beam right quadrant operation location approximately 6 (forward or reverse effect), and supply pressure to the fisher valve positioner. Arm as shown in the figure below, the rotation 0 degrees indexing tags should be aligned to the shell index mark, and between the actuator shall be located in the position. If not, first check whether the connecting rod is loose or CAM improperly installed. May need to fine tune the nozzle height, in order to make the required values ​​of the input signal and the starting point of the journey.

Step 3. Apply a is equal to the input signal range lower limit value of the input signal. If your locator is 0.2 bar to 1.2 bar range (3 to 15 psig) input range, please set the input for 3 psig. Loosen the nozzle lock nut and adjust the nozzle until the actuator move to the right end of the trip. Change the nozzle position only as a means of zero fine-tuning adjustments. When the nozzle location changes, the zero reference point will change.

Step 4. Places a high value is equal to the input signal range input signal (15 psig, if use 3 to 15 psig locator) actuators push rod stroke were observed. If the valve stem schedule below its expected range, through mobile baffle components to beam to increase the number of higher on schedule. If needed to stem stroke occurred in the input signal to input signal range of high value, by the baffle component to a lower number on the beam moving to reduce the itinerary.

Step 5. Repeat steps 3 and 4, until you reach the correct schedule. Every time a change in step 4 baffle component position, repeat steps 3 to provide a proper zero. Please note that the baffle components in the beam scale to hold zero mobile will reduce stem travel.