Calibration Fisher DVC6200 Positioners

Based on our professional engineering control valve experience, we would detail the operational principles, technical specifications, and steps for troubleshooting or calibrating the Fisher DVC6200 positioner. This device is commonly used in industrial applications to control valve positions, ensuring precision and efficiency in fluid handling systems. This article includes information on how the positioner interprets control signals, adjusts valve positions accordingly, and the feedback mechanisms it employs to maintain control accuracy. Additionally, debugging sections would cover common issues, diagnostic procedures, and adjustment techniques to ensure optimal performance.

The Fisher DVC6200 Digital Valve Controllers, abbreviated as DVC, represent a series model in the development of Fisher’s DVC positioners. The DVC6200 is developed by integrating the features of the DVC2000 and DVC6000 series, resulting in a valve positioner that boasts high applicability and reliability.

What is DVC6200 Positioner

The Fisher DVC6200 digital positioner with the 67CFR filter regulator designed for pneumatic control valves, such as model ET, EZ, EWT etc,.

The FIELDVUE DVC6200 system enhances operational efficiency by enabling more precise control, thereby driving the process closer to its setpoint and significantly enhancing product quality. Leveraging FIELDVUE Performance Diagnostics, this instrument offers real-time valve operation monitoring to assess performance and reliability meticulously.

DVC6200 Digital Positioner Specifications

• Area Classification: Designed to meet rigorous standards, including Explosion Proof, Intrinsically Safe, FISCO, Type N, Flame Proof, and Non-incendive for FM.
• Certifications: Comprehensive certifications such as CSA, FM, ATEX, IECEx, CUTR, Lloyd’s Register, Peso, KGS, INMETRO, NEPSI, TIIS, certified for Natural Gas, and recognized as a Single Seal Device.
• Communication Protocol: Utilizes HART® 4-20 mA for reliable data transmission.
• Data Interface: Offers a wired connection for secure data communication.
• Diagnostics: Embedded diagnostics for enhanced performance monitoring.
• Input Signal: Electric, ensuring versatile applicability.
• Max Outlet Pressure: Capable of reaching up to 145 psig.
• Mounting Type: Features an integral mounting design.
• Operating Temperature: Supports both standard and high-temperature operations.
• Position Control: Offers throttling control and on/off capabilities.
• Power Source: Operates with a local power source.
• Process Control: Facilitates control over flow, pressure, temperature, and level.
• Supply Media: Compatible with air, natural gas, and nitrogen.

For additional configurations and specifications, we encourage you to consult with your local Emerson business partner or sales office.

DVC6200 Digital Features

1. The DVC6200 features a high-performance, linkage-less feedback system, which eliminates wear on parts by avoiding physical contact.
2. Its fully encapsulated electronics are designed to withstand vibration, temperature fluctuations, and corrosive environments.
3. Offers rapid response to significant step changes and delivers precise control over minor setpoint adjustments.
4. As a HART communicating device, the DVC6200 ensures easy access to information throughout the loop, minimizing the need for direct interaction in hazardous environments and simplifying valve evaluations in difficult-to-access areas.
5. Its modular design permits the replacement of critical components without the need to disconnect field wiring or pneumatic tubing.
6. Integration into control systems can yield considerable savings on hardware and installation costs.
7. The self-diagnostic feature of the DVC6200 offers comprehensive insights into valve performance and health, ensuring optimal operation.
8. Digital communication enhances the accessibility of valve conditions, facilitating maintenance and operation.

Instrument Level Capabilities of Fisher DVC6200 Digital Valve Controller

Principle of the DVC6200 Double Acting Digital Positioner

The input control signal of 4-20mA DC from the control system is transmitted via signal lines to the terminal box. The electronic module processor within the positioner reads the input control signal and the valve position feedback signal. After digital processing, it converts these signals into an analog control drive signal for the I/P electrical converter. The I/P converter then transforms the electrical signal into a pneumatic signal, which is power amplified by a pneumatic amplifier, providing two pneumatic outputs.

For instance, as the signal increases, the air pressure at output A increases while the air pressure at output B decreases. When the signal is set to 12mA, the air pressures at outputs A and B are approximately equal. Conversely, when the signal decreases, the air source at output B increases, and the air source at output A decreases. The pneumatic output from the digital valve positioner is then directed to the pneumatic actuator of the control valve, causing the valve stem position to change. Consequently, the position of the magnetic strip also changes. A Hall sensor detects this change in valve position and sends the signal back to the electronic module. The positioning control process concludes when the valve position aligns with the input control signal, stabilizing the signal from the I/P electrical converter and the output air pressure from the pneumatic amplifier, with minimal deviation.

Difference of Digital Positioner DVC6200 Terminal Box with Feedback Signal or Not

The I/P Electrical Converter—Transforms Electrical Signals into Pneumatic Signals

The air supply passes through a constant throttle orifice (constant air resistance) to the nozzle. The drive signal from the electronic module controls the coil of the I/P converter, attracting the armature to act. This movement of the armature moves the flapper closer to the nozzle, causing an increase in the back pressure at the nozzle. This increase translates to a higher pneumatic signal sent to the pneumatic amplifier, ultimately resulting in an increase in the output air pressure from the valve positioner. When the drive signal is reduced, the electromagnetic coil causes the armature/flapper to move away from the nozzle, reducing its back pressure and, consequently, the output from the pneumatic amplifier decreases.

How to Install Fisher Digital Positioner DVC6200

How to Install and Assembly DVC6200 to Sliding Stem/Linear Type Control Valves

How to Install and Assembly DVC6200 to Rotary Type Control Valves

How Use 375 Or 475 Field Communicator To Calibrate Fisher DVC6200 Digital Positioner

Step 1. Initial Connection

1. Connect a HART® communicator to the DVC6200, ensuring it is in parallel with a 4-20 mA loop across the “loop” terminals.
2. Apply a 4 mA signal to the DVC6200 and activate the HART communicator.

Step 2. Switching Instrument Mode

• Navigate to the instrument’s menu and select ‘Configure’, followed by ‘Detailed Setup’, then ‘Mode and Protection’, and finally ‘Instrument Mode’.
• Select “Not in Service” and confirm by pressing ‘Enter’.
• To return to the main menu, press the home key.

Step 3. Commencing Configuration

• Proceed by selecting ‘Configure’, then ‘Guided Setup’, followed by ‘Setup Wizard’.
• The ‘Setup Wizard’ will initiate a series of configuration prompts. You will be asked to provide details about the actuator and valve, including the manufacturer, type, size, and supply pressure requirements.

Step 4. Factory Defaults and Setup Wizard Completion

• When prompted, opt to send the factory defaults as an initial setting. Note that fine-tuning adjustments can be made subsequently.
• Complete the setup wizard as instructed by the communicator, which will then direct you to initiate the auto-travel calibration process.

Step 5. Auto-Travel Calibration

• Select the manual method when prompted for the adjustment method for output bias.
• The communicator will automatically actuate the valve to both 100% and 0% travel, adjusting the output bias accordingly.
• Upon reaching the prompt for 50%, adjust the mA input to 12 mA and continue with the auto-travel calibration as instructed.

Step 6. Finalizing Configuration

• Following the auto-travel calibration, the communicator will prompt a return to “In Service” mode. Comply with this request.
• Perform a complete valve stroke to ensure that the valve opens linearly in response to the 4-20 mA input signal.

This process is designed to ensure that your DVC6200 controller is calibrated accurately and operates efficiently. For optimal performance, adhere closely to each step and make adjustments as necessary based on the specific requirements of your actuator and valve configuration. Should you have any questions, please feel free to contact TKLD's  consultation team.