Emerson Fisher FIELDVUE DVC6000f, Инструкция по эксплуатации

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DVC6000f Digital Valve Controllers
December 2009 7-6
Figure 7-2. Back View of PWB Assembly Sub-Module
GE39341
PINS REMOVED FOR
CONNECTOR KEYING
TERMINAL BOX
CONNECTOR
TRAVEL
SENSOR
CONNECTOR
3. Connect the travel sensor connector to the PWB
assembly (key 50). The connector is keyed, so proper
orientation is required.
4. Insert the module base (key 2) into the housing
(key 1).
5. Install three socket head screws (key 38) in the
module base into the housing. If not already installed,
press three retaining rings (key 154) into the module
base. Evenly tighten the screws in a crisscross pattern
to a final torque of 16 N
m (138 lbf in).
6. Attach the cover (key 43) to the module base
assembly.
7. For sliding-stem applications only, install the
protective shield onto the side of the replacement
module base assembly (see figures 2-1 and 2-2).
Submodule Maintenance
WARNING
To avoid personal injury or property
damage caused by fire or explosion,
remove power to the instrument
before replacing a submodule in an
area which contains a potentially
explosive atmosphere or has been
classified as hazardous.
The digital valve controller’s module base contains the
following submodules: I/P converter, PWB assembly,
and pneumatic relay. If problems occur, these
submodules may be removed from the module base
and replaced with new submodules. After replacing a
submodule, the module base is replaced in the
instrument and calibrated prior to returning to service.
CAUTION
Exercise care when performing
maintenance on the module base.
Reinstall the cover to protect the I/P
converter and gauges when servicing
other submodules.
In order to maintain accuracy
specifications, do not strike or drop
the I/P converter during submodule
maintenance.
I/P Converter
Refer to figures 8-2 through 8-6 for key number
locations. The I/P converter (key 41) is located on the
front of the module base.
Note
After I/P converter submodule
replacement, calibrate the digital valve
controller to maintain accuracy
specifications.
Replacing the I/P Filter
A screen in the supply port beneath the I/P converter
serves as a secondary filter for the supply medium. To
replace this filter, perform the following procedure:
1. Remove the I/P converter (key 41) and shroud
(key 169) as described in the Removing the I/P
Converter procedure.
2. Remove the screen (key 231) from the supply port.
3. Install a new screen in the supply port as shown in
figure 7-3.
4. Inspect the O-ring (key 39) in the I/P output port. if
necessary, replace it.
5. Reinstall the I/P converter (key 41) and shroud (key
169) as described in the Replacing the I/P Converter
procedure.
Removing the I/P Converter
1. Remove the front cover (key 43), if not already
removed.
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