Emerson Fisher FIELDVUE DVC6000, Инструкция по эксплуатации

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DVC6000 Digital Valve Controllers
September 2013 2-8
Note
When performing the following steps,
ensure there is enough clearance
between the adjustment arm and the
feedback arm to prevent interference
with the bias spring.
7. Apply anti-seize (key 64) to the pin of the
adjustment arm. As shown in figure 2-3, place the pin
into the slot of the feedback arm or feedback arm
extension so that the bias spring loads the pin against
the side of the arm with the valve travel markings.
8. Install the external lock washer on the adjustment
arm. Position the adjustment arm in the slot of the
connector arm and loosely install the flanged hex nut.
9. Slide the adjustment arm pin in the slot of the
connector arm until the pin is in line with the desired
valve travel marking. Tighten the flanged hex nut.
10. Remove the alignment pin (key 46) and store it in
the module base next to the I/P assembly.
11. After calibrating the instrument, attach the shield
with two machine screws.
DVC6020 on Long-Stroke (4 to 24 Inch
Travel) Sliding-Stem Actuators and
Rotary Actuators
If ordered as part of a control valve assembly, the
factory mounts the digital valve controller on the
actuator, makes pneumatic connections to the
actuator, sets up, and calibrates the instrument. If you
purchased the digital valve controller separately, you
will need a mounting kit to mount the digital valve
controller on the actuator. See the instructions that
come with the mounting kit for detailed information on
mounting the digital valve controller to a specific
actuator model.
Note
All cams supplied with FIELDVUE
mounting kits are characterized to
provide a linear response.
Note
Do not use the stainless steel
DVC6020S in high vibration service
where the mounting bracket uses
standoffs (spacers) to mount to the
actuator.
DVC6020 digital valve controllers use a cam (designed
for linear response) and roller as the feedback
mechanism. Figure 2-4 shows an example of
mounting on sliding-stem actuators with travels from 4
inches to 24 inches. Some long-stroke applications will
require an actuator with a tapped lower yoke boss.
Figures 2-5 and 2-6 show the DVC6020 mounted on
rotary actuators.
As shown in figure 2-5, two feedback arms are
available for the digital valve controller. Most
long-stroke sliding-stem and rotary actuator
installations use the long feedback arm [62 mm (2.45
inches) from roller to pivot point]. Installations on
Fisher 1051 size 33 and 1052 size 20 and 33
actuators use the short feedback arm [54 mm (2.13
inches) from roller to pivot point]. Make sure the
correct feedback arm is installed on the digital valve
controller before beginning the mounting procedure.
Refer to figures 2-4, 2-5, and 2-6 for parts locations.
Also, where a key number is referenced, refer to figure
8-3. Refer to the following guidelines when mounting
on sliding-stem actuators with 4 to 24 inches of travel
or on rotary actuators:
1. Isolate the control valve from the process line
pressure and release pressure from both sides of the
valve body. Shut off all pressure lines to the
pneumatic actuator, releasing all pressure from the
actuator. Use lock-out procedures to be sure that the
above measures stay in effect while working on the
equipment.
2. If a cam is not already installed on the actuator,
install the cam as described in the instructions
included with the mounting kit. For sliding-stem
actuators, the cam is installed on the stem connector.
3. If a mounting plate is required, fasten the mounting
plate to the actuator.
4. For applications that require remote venting, a
pipe-away bracket kit is available. Follow the
instructions included with the kit to replace the existing
mounting bracket on the digital valve controller with
the pipe-away bracket and to transfer the feedback
parts from the existing mounting bracket to the
pipe-away bracket.
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